content/browser/renderer_host/input/wheel_scroll_latching_browsertest.cc - chromium/src - Git at Google

 // Copyright 2017 The Chromium Authors
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.

 #include "base/run_loop.h"
 #include "base/task/single_thread_task_runner.h"
 #include "build/build_config.h"
 #include "components/input/render_widget_host_input_event_router.h"
 #include "content/browser/renderer_host/render_widget_host_impl.h"
 #include "content/browser/web_contents/web_contents_impl.h"
 #include "content/public/test/browser_test.h"
 #include "content/public/test/browser_test_utils.h"
 #include "content/public/test/content_browser_test.h"
 #include "content/public/test/content_browser_test_utils.h"
 #include "content/public/test/hit_test_region_observer.h"
 #include "content/shell/browser/shell.h"
 #include "third_party/blink/public/common/input/synthetic_web_input_event_builders.h"
 #include "ui/events/gesture_detection/gesture_configuration.h"

 #if BUILDFLAG(IS_ANDROID)
 #include "content/browser/renderer_host/render_widget_host_view_android.h"
 #endif

 using blink::WebMouseWheelEvent;

 namespace {
 void GiveItSomeTime() {
   base::RunLoop run_loop;
   base::SingleThreadTaskRunner::GetCurrentDefault()->PostDelayedTask(
       FROM_HERE, run_loop.QuitClosure(), base::Milliseconds(20));
   run_loop.Run();
 }

 const char kWheelEventLatchingDataURL[] = R"HTML(
     <!DOCTYPE html>
     <meta name='viewport' content='width=device-width, minimum-scale=1'>
     <style>
     body {
       height: 10000px;
     }
     %23scrollableDiv {
       position: absolute;
       left: 50px;
       top: 100px;
       width: 200px;
       height: 200px;
       overflow: scroll;
       background: red;
     }
     %23nestedDiv {
       width: 200px;
       height: 8000px;
       opacity: 0;
     }
     </style>
     <div id='scrollableDiv'>
      <div id='nestedDiv'></div>
     </div>
     <script>
       var scrollableDiv = document.getElementById('scrollableDiv');
       var scrollableDivWheelEventCounter = 0;
       var documentWheelEventCounter = 0;
       scrollableDiv.addEventListener('wheel',
         function(e) {
           scrollableDivWheelEventCounter++;
           e.stopPropagation();
         });
       document.scrollingElement.addEventListener('wheel',
         function(e) { documentWheelEventCounter++; });
     </script>)HTML";
 }  // namespace

 namespace content {
 class WheelScrollLatchingBrowserTest : public ContentBrowserTest {
  public:
   WheelScrollLatchingBrowserTest() {
     ui::GestureConfiguration::GetInstance()->set_scroll_debounce_interval_in_ms(
         0);
   }
   ~WheelScrollLatchingBrowserTest() override {}

  protected:
   RenderWidgetHostImpl* GetWidgetHost() {
     return RenderWidgetHostImpl::From(
         web_contents()->GetRenderViewHost()->GetWidget());
   }

   WebContentsImpl* web_contents() const {
     return static_cast<WebContentsImpl*>(shell()->web_contents());
   }

   input::RenderWidgetHostInputEventRouter* GetRouter() {
     return web_contents()->GetInputEventRouter();
   }

   RenderWidgetHostViewBase* GetRootView() {
     return static_cast<RenderWidgetHostViewBase*>(web_contents()
                                                       ->GetPrimaryFrameTree()
                                                       .root()
                                                       ->current_frame_host()
                                                       ->GetView());
   }

   void LoadURL(const std::string& page_data) {
     const GURL data_url("data:text/html;charset=utf-8," + page_data);
     EXPECT_TRUE(NavigateToURL(shell(), data_url));

     RenderWidgetHostImpl* host = GetWidgetHost();
     host->GetView()->SetSize(gfx::Size(600, 600));

     // The page is loaded in the renderer, wait for a new frame to arrive.
     // That's equivalent to hit test data being ready.
     HitTestRegionObserver hittest_observer(host->GetFrameSinkId());
     hittest_observer.WaitForHitTestData();
   }
 };

 // Start scrolling by mouse wheel on the document: the wheel event will be sent
 // to the document's scrolling element, the scrollable div will be under the
 // cursor after applying the scrolling. Continue scrolling by mouse wheel, since
 // wheel scroll latching is enabled the wheel event will be still sent to the
 // document's scrolling element and the document's scrolling element will
 // continue scrolling.
 IN_PROC_BROWSER_TEST_F(WheelScrollLatchingBrowserTest, WheelEventTarget) {
   LoadURL(kWheelEventLatchingDataURL);
   EXPECT_EQ(0, EvalJs(shell(), "documentWheelEventCounter"));
   EXPECT_EQ(0, EvalJs(shell(), "scrollableDivWheelEventCounter"));

   MainThreadFrameObserver frame_observer(GetWidgetHost());

   auto input_msg_watcher = std::make_unique<InputMsgWatcher>(
       GetWidgetHost(), blink::WebInputEvent::Type::kMouseWheel);

   float scrollable_div_top =
       EvalJs(shell(), "scrollableDiv.getBoundingClientRect().top")
           .ExtractDouble();
   float x = (EvalJs(shell(), "scrollableDiv.getBoundingClientRect().left")
                  .ExtractDouble() +
              EvalJs(shell(), "scrollableDiv.getBoundingClientRect().right")
                  .ExtractDouble()) /
             2;
   float y = 0.1 * scrollable_div_top;
   float delta_x = 0;
   float delta_y = -0.6 * scrollable_div_top;
   blink::WebMouseWheelEvent wheel_event =
       blink::SyntheticWebMouseWheelEventBuilder::Build(
           x, y, x, y, delta_x, delta_y, 0,
           ui::ScrollGranularity::kScrollByPrecisePixel);

   wheel_event.phase = blink::WebMouseWheelEvent::kPhaseBegan;
   GetRouter()->RouteMouseWheelEvent(GetRootView(), &wheel_event,
                                     ui::LatencyInfo());

   // Runs until we get the InputMsgAck callback.
   EXPECT_EQ(blink::mojom::InputEventResultState::kSetNonBlocking,
             input_msg_watcher->WaitForAck());

   while (
       EvalJs(shell(), "document.scrollingElement.scrollTop").ExtractDouble() <
       -delta_y) {
     frame_observer.Wait();
   }

   EXPECT_EQ(0, EvalJs(shell(), "scrollableDiv.scrollTop"));
   EXPECT_EQ(1, EvalJs(shell(), "documentWheelEventCounter"));
   EXPECT_EQ(0, EvalJs(shell(), "scrollableDivWheelEventCounter"));

   wheel_event.phase = blink::WebMouseWheelEvent::kPhaseChanged;
   GetRouter()->RouteMouseWheelEvent(GetRootView(), &wheel_event,
                                     ui::LatencyInfo());

   while (
       EvalJs(shell(), "document.scrollingElement.scrollTop").ExtractDouble() <
       -2 * delta_y) {
     frame_observer.Wait();
   }
   EXPECT_EQ(0, EvalJs(shell(), "scrollableDiv.scrollTop"));
   EXPECT_EQ(2, EvalJs(shell(), "documentWheelEventCounter"));
   EXPECT_EQ(0, EvalJs(shell(), "scrollableDivWheelEventCounter"));
 }

 // TODO(crbug.com/1248231, crbug.com/1313237): consider removing this test.
 IN_PROC_BROWSER_TEST_F(WheelScrollLatchingBrowserTest,
                        DISABLED_WheelEventRetargetWhenTargetRemoved) {
   LoadURL(kWheelEventLatchingDataURL);
   EXPECT_EQ(0, EvalJs(shell(), "documentWheelEventCounter"));
   EXPECT_EQ(0, EvalJs(shell(), "scrollableDivWheelEventCounter"));

   auto update_msg_watcher = std::make_unique<InputMsgWatcher>(
       GetWidgetHost(), blink::WebInputEvent::Type::kGestureScrollUpdate);

   float scrollable_div_top =
       EvalJs(shell(), "scrollableDiv.getBoundingClientRect().top")
           .ExtractDouble();
   float x = (EvalJs(shell(), "scrollableDiv.getBoundingClientRect().left")
                  .ExtractDouble() +
              EvalJs(shell(), "scrollableDiv.getBoundingClientRect().right")
                  .ExtractDouble()) /
             2;
   float y = 1.1 * scrollable_div_top;
   float delta_x = 0;
   float delta_y = -0.6 * scrollable_div_top;
   blink::WebMouseWheelEvent wheel_event =
       blink::SyntheticWebMouseWheelEventBuilder::Build(
           x, y, x, y, delta_x, delta_y, 0,
           ui::ScrollGranularity::kScrollByPrecisePixel);
   wheel_event.phase = blink::WebMouseWheelEvent::kPhaseBegan;
   GetRouter()->RouteMouseWheelEvent(GetRootView(), &wheel_event,
                                     ui::LatencyInfo());

   // Runs until we get the UpdateMsgAck callback.
   EXPECT_EQ(blink::mojom::InputEventResultState::kConsumed,
             update_msg_watcher->WaitForAck());

   EXPECT_EQ(0, EvalJs(shell(), "document.scrollingElement.scrollTop"));
   EXPECT_EQ(0, EvalJs(shell(), "documentWheelEventCounter"));
   EXPECT_EQ(1, EvalJs(shell(), "scrollableDivWheelEventCounter"));

   // Remove the scrollableDiv which is the current target for wheel events.
   EXPECT_TRUE(
       ExecJs(shell(), "scrollableDiv.parentNode.removeChild(scrollableDiv)"));

   wheel_event.phase = blink::WebMouseWheelEvent::kPhaseChanged;
   GetRouter()->RouteMouseWheelEvent(GetRootView(), &wheel_event,
                                     ui::LatencyInfo());

   // Runs until we get the UpdateMsgAck callbacks.
   EXPECT_EQ(blink::mojom::InputEventResultState::kConsumed,
             update_msg_watcher->WaitForAck());

   // Wait for the document event listenr to handle the second wheel event.
   while (EvalJs(shell(), "documentWheelEventCounter") != 1) {
     GiveItSomeTime();
   }

   EXPECT_EQ(1, EvalJs(shell(), "scrollableDivWheelEventCounter"));
 }

 // crbug.com/777258 Flaky everywhere.
 IN_PROC_BROWSER_TEST_F(
     WheelScrollLatchingBrowserTest,
     DISABLED_WheelScrollingRelatchWhenLatchedScrollerRemoved) {
   LoadURL(kWheelEventLatchingDataURL);
   EXPECT_EQ(EvalJs(shell(), "document.scrollingElement.scrollTop"), 0);
   EXPECT_EQ(EvalJs(shell(), "scrollableDiv.scrollTop"), 0);
   float x = (EvalJs(shell(), "scrollableDiv.getBoundingClientRect().left")
                  .ExtractDouble() +
              EvalJs(shell(), "scrollableDiv.getBoundingClientRect().right")
                  .ExtractDouble()) /
             2;
   float y = (EvalJs(shell(), "scrollableDiv.getBoundingClientRect().top")
                  .ExtractDouble() +
              EvalJs(shell(), "scrollableDiv.getBoundingClientRect().bottom")
                  .ExtractDouble()) /
             2;
 #if BUILDFLAG(IS_CHROMEOS)
   bool precise = true;
 #else
   bool precise = false;
 #endif
   // Send a GSB event to start scrolling the scrollableDiv.
   blink::WebGestureEvent gesture_scroll_begin(
       blink::WebGestureEvent::Type::kGestureScrollBegin,
       blink::WebInputEvent::kNoModifiers,
       blink::WebInputEvent::GetStaticTimeStampForTests(),
       blink::WebGestureDevice::kTouchpad);
   gesture_scroll_begin.data.scroll_begin.delta_hint_units =
       precise ? ui::ScrollGranularity::kScrollByPrecisePixel
               : ui::ScrollGranularity::kScrollByPixel;
   gesture_scroll_begin.data.scroll_begin.delta_x_hint = 0.f;
   gesture_scroll_begin.data.scroll_begin.delta_y_hint = -20.f;
   gesture_scroll_begin.SetPositionInWidget(gfx::PointF(x, y));
   gesture_scroll_begin.SetPositionInScreen(gfx::PointF(x, y));
   GetRootView()->ProcessGestureEvent(gesture_scroll_begin, ui::LatencyInfo());

   // Send the first GSU event.
   blink::WebGestureEvent gesture_scroll_update(gesture_scroll_begin);
   gesture_scroll_update.SetType(
       blink::WebGestureEvent::Type::kGestureScrollUpdate);
   gesture_scroll_update.data.scroll_update.delta_units =
       precise ? ui::ScrollGranularity::kScrollByPrecisePixel
               : ui::ScrollGranularity::kScrollByPixel;
   gesture_scroll_update.data.scroll_update.delta_x = 0.f;
   gesture_scroll_update.data.scroll_update.delta_y = -20.f;
   GetRootView()->ProcessGestureEvent(gesture_scroll_update, ui::LatencyInfo());

   // Wait for the scrollableDiv to scroll.
   while (EvalJs(shell(), "scrollableDiv.scrollTop") < 20) {
     GiveItSomeTime();
   }

   // Remove the scrollableDiv which is the current scroller and send the second
   // GSU.
   EXPECT_TRUE(
       ExecJs(shell(), "scrollableDiv.parentNode.removeChild(scrollableDiv)"));
   GiveItSomeTime();
   GetRootView()->ProcessGestureEvent(gesture_scroll_update, ui::LatencyInfo());
   while (EvalJs(shell(), "document.scrollingElement.scrollTop") < 20) {
     GiveItSomeTime();
   }
 }

 const char kWheelRetargetIfPreventedByDefault[] = R"HTML(
     <!DOCTYPE html>
     <meta name='viewport' content='width=device-width, minimum-scale=1'>
     <style>
     %23blueDiv {
       position: absolute;
       left: 50px;
       top: 100px;
       width: 200px;
       height: 200px;
       display: block;
       background: blue;
     }
     %23redDiv {
       width: 200px;
       height: 200px;
       display: none;
       background: red;
     }
     </style>
     <body>
       <div id='blueDiv'>
         <div id='redDiv'></div>
       </div>
     </body>
     <script>
     var blueDiv = document.getElementById('blueDiv');
     var redDiv = document.getElementById('redDiv');
     var domTarget = 'noTarget';
     var x = (blueDiv.getBoundingClientRect().left +
         blueDiv.getBoundingClientRect().right) / 2;
     var y = (blueDiv.getBoundingClientRect().top +
         blueDiv.getBoundingClientRect().bottom) /2;
     blueDiv.addEventListener('wheel', function(e) {
       e.preventDefault();
       domTarget = 'blueDiv';
       redDiv.style.display = 'block';
     });
     redDiv.addEventListener('wheel', function(e) {
       domTarget = 'redDiv';
       e.stopPropagation();
     });
     </script>)HTML";

 IN_PROC_BROWSER_TEST_F(WheelScrollLatchingBrowserTest,
                        WheelEventRetargetOnPreventDefault) {
   LoadURL(kWheelRetargetIfPreventedByDefault);

   float x = EvalJs(shell(), "x").ExtractDouble();
   float y = EvalJs(shell(), "y").ExtractDouble();

   // Send the first wheel event.
   auto wheel_msg_watcher = std::make_unique<InputMsgWatcher>(
       GetWidgetHost(), blink::WebInputEvent::Type::kMouseWheel);
   blink::WebMouseWheelEvent wheel_event =
       blink::SyntheticWebMouseWheelEventBuilder::Build(
           x, y, x, y, 1, 1, 0, ui::ScrollGranularity::kScrollByPrecisePixel);
   wheel_event.phase = blink::WebMouseWheelEvent::kPhaseBegan;
   GetRouter()->RouteMouseWheelEvent(GetRootView(), &wheel_event,
                                     ui::LatencyInfo());

   // Run until we get the callback, then check the target.
   EXPECT_EQ(blink::mojom::InputEventResultState::kConsumed,
             wheel_msg_watcher->WaitForAck());
   EXPECT_EQ("blueDiv", EvalJs(shell(), "domTarget"));

   // Send the second wheel event.
   wheel_msg_watcher = std::make_unique<InputMsgWatcher>(
       GetWidgetHost(), blink::WebInputEvent::Type::kMouseWheel);
   wheel_event.phase = blink::WebMouseWheelEvent::kPhaseChanged;
   GetRouter()->RouteMouseWheelEvent(GetRootView(), &wheel_event,
                                     ui::LatencyInfo());

   // Run until we get the callback, then check the target.
   EXPECT_EQ(blink::mojom::InputEventResultState::kNotConsumed,
             wheel_msg_watcher->WaitForAck());
   EXPECT_EQ("redDiv", EvalJs(shell(), "domTarget"));
 }

 }  // namespace content
	// Copyright 2017 The Chromium Authors
	// Use of this source code is governed by a BSD-style license that can be
	// found in the LICENSE file.

	#include "base/run_loop.h"
	#include "base/task/single_thread_task_runner.h"
	#include "build/build_config.h"
	#include "components/input/render_widget_host_input_event_router.h"
	#include "content/browser/renderer_host/render_widget_host_impl.h"
	#include "content/browser/web_contents/web_contents_impl.h"
	#include "content/public/test/browser_test.h"
	#include "content/public/test/browser_test_utils.h"
	#include "content/public/test/content_browser_test.h"
	#include "content/public/test/content_browser_test_utils.h"
	#include "content/public/test/hit_test_region_observer.h"
	#include "content/shell/browser/shell.h"
	#include "third_party/blink/public/common/input/synthetic_web_input_event_builders.h"
	#include "ui/events/gesture_detection/gesture_configuration.h"

	#if BUILDFLAG(IS_ANDROID)
	#include "content/browser/renderer_host/render_widget_host_view_android.h"
	#endif

	using blink::WebMouseWheelEvent;

	namespace {
	void GiveItSomeTime() {
	base::RunLoop run_loop;
	base::SingleThreadTaskRunner::GetCurrentDefault()->PostDelayedTask(
	FROM_HERE, run_loop.QuitClosure(), base::Milliseconds(20));
	run_loop.Run();
	}

	const char kWheelEventLatchingDataURL[] = R"HTML(
	<!DOCTYPE html>
	<meta name='viewport' content='width=device-width, minimum-scale=1'>
	<style>
	body {
	height: 10000px;
	}
	%23scrollableDiv {
	position: absolute;
	left: 50px;
	top: 100px;
	width: 200px;
	height: 200px;
	overflow: scroll;
	background: red;
	}
	%23nestedDiv {
	width: 200px;
	height: 8000px;
	opacity: 0;
	}
	</style>
	<div id='scrollableDiv'>
	<div id='nestedDiv'></div>
	</div>
	<script>
	var scrollableDiv = document.getElementById('scrollableDiv');
	var scrollableDivWheelEventCounter = 0;
	var documentWheelEventCounter = 0;
	scrollableDiv.addEventListener('wheel',
	function(e) {
	scrollableDivWheelEventCounter++;
	e.stopPropagation();
	});
	document.scrollingElement.addEventListener('wheel',
	function(e) { documentWheelEventCounter++; });
	</script>)HTML";
	} // namespace

	namespace content {
	class WheelScrollLatchingBrowserTest : public ContentBrowserTest {
	public:
	WheelScrollLatchingBrowserTest() {
	ui::GestureConfiguration::GetInstance()->set_scroll_debounce_interval_in_ms(
	0);
	}
	~WheelScrollLatchingBrowserTest() override {}

	protected:
	RenderWidgetHostImpl* GetWidgetHost() {
	return RenderWidgetHostImpl::From(
	web_contents()->GetRenderViewHost()->GetWidget());
	}

	WebContentsImpl* web_contents() const {
	return static_cast<WebContentsImpl*>(shell()->web_contents());
	}

	input::RenderWidgetHostInputEventRouter* GetRouter() {
	return web_contents()->GetInputEventRouter();
	}

	RenderWidgetHostViewBase* GetRootView() {
	return static_cast<RenderWidgetHostViewBase*>(web_contents()
	->GetPrimaryFrameTree()
	.root()
	->current_frame_host()
	->GetView());
	}

	void LoadURL(const std::string& page_data) {
	const GURL data_url("data:text/html;charset=utf-8," + page_data);
	EXPECT_TRUE(NavigateToURL(shell(), data_url));

	RenderWidgetHostImpl* host = GetWidgetHost();
	host->GetView()->SetSize(gfx::Size(600, 600));

	// The page is loaded in the renderer, wait for a new frame to arrive.
	// That's equivalent to hit test data being ready.
	HitTestRegionObserver hittest_observer(host->GetFrameSinkId());
	hittest_observer.WaitForHitTestData();
	}
	};

	// Start scrolling by mouse wheel on the document: the wheel event will be sent
	// to the document's scrolling element, the scrollable div will be under the
	// cursor after applying the scrolling. Continue scrolling by mouse wheel, since
	// wheel scroll latching is enabled the wheel event will be still sent to the
	// document's scrolling element and the document's scrolling element will
	// continue scrolling.
	IN_PROC_BROWSER_TEST_F(WheelScrollLatchingBrowserTest, WheelEventTarget) {
	LoadURL(kWheelEventLatchingDataURL);
	EXPECT_EQ(0, EvalJs(shell(), "documentWheelEventCounter"));
	EXPECT_EQ(0, EvalJs(shell(), "scrollableDivWheelEventCounter"));

	MainThreadFrameObserver frame_observer(GetWidgetHost());

	auto input_msg_watcher = std::make_unique<InputMsgWatcher>(
	GetWidgetHost(), blink::WebInputEvent::Type::kMouseWheel);

	float scrollable_div_top =
	EvalJs(shell(), "scrollableDiv.getBoundingClientRect().top")
	.ExtractDouble();
	float x = (EvalJs(shell(), "scrollableDiv.getBoundingClientRect().left")
	.ExtractDouble() +
	EvalJs(shell(), "scrollableDiv.getBoundingClientRect().right")
	.ExtractDouble()) /
	2;
	float y = 0.1 * scrollable_div_top;
	float delta_x = 0;
	float delta_y = -0.6 * scrollable_div_top;
	blink::WebMouseWheelEvent wheel_event =
	blink::SyntheticWebMouseWheelEventBuilder::Build(
	x, y, x, y, delta_x, delta_y, 0,
	ui::ScrollGranularity::kScrollByPrecisePixel);

	wheel_event.phase = blink::WebMouseWheelEvent::kPhaseBegan;
	GetRouter()->RouteMouseWheelEvent(GetRootView(), &wheel_event,
	ui::LatencyInfo());

	// Runs until we get the InputMsgAck callback.
	EXPECT_EQ(blink::mojom::InputEventResultState::kSetNonBlocking,
	input_msg_watcher->WaitForAck());

	while (
	EvalJs(shell(), "document.scrollingElement.scrollTop").ExtractDouble() <
	-delta_y) {
	frame_observer.Wait();
	}

	EXPECT_EQ(0, EvalJs(shell(), "scrollableDiv.scrollTop"));
	EXPECT_EQ(1, EvalJs(shell(), "documentWheelEventCounter"));
	EXPECT_EQ(0, EvalJs(shell(), "scrollableDivWheelEventCounter"));

	wheel_event.phase = blink::WebMouseWheelEvent::kPhaseChanged;
	GetRouter()->RouteMouseWheelEvent(GetRootView(), &wheel_event,
	ui::LatencyInfo());

	while (
	EvalJs(shell(), "document.scrollingElement.scrollTop").ExtractDouble() <
	-2 * delta_y) {
	frame_observer.Wait();
	}
	EXPECT_EQ(0, EvalJs(shell(), "scrollableDiv.scrollTop"));
	EXPECT_EQ(2, EvalJs(shell(), "documentWheelEventCounter"));
	EXPECT_EQ(0, EvalJs(shell(), "scrollableDivWheelEventCounter"));
	}

	// TODO(crbug.com/1248231, crbug.com/1313237): consider removing this test.
	IN_PROC_BROWSER_TEST_F(WheelScrollLatchingBrowserTest,
	DISABLED_WheelEventRetargetWhenTargetRemoved) {
	LoadURL(kWheelEventLatchingDataURL);
	EXPECT_EQ(0, EvalJs(shell(), "documentWheelEventCounter"));
	EXPECT_EQ(0, EvalJs(shell(), "scrollableDivWheelEventCounter"));

	auto update_msg_watcher = std::make_unique<InputMsgWatcher>(
	GetWidgetHost(), blink::WebInputEvent::Type::kGestureScrollUpdate);

	float scrollable_div_top =
	EvalJs(shell(), "scrollableDiv.getBoundingClientRect().top")
	.ExtractDouble();
	float x = (EvalJs(shell(), "scrollableDiv.getBoundingClientRect().left")
	.ExtractDouble() +
	EvalJs(shell(), "scrollableDiv.getBoundingClientRect().right")
	.ExtractDouble()) /
	2;
	float y = 1.1 * scrollable_div_top;
	float delta_x = 0;
	float delta_y = -0.6 * scrollable_div_top;
	blink::WebMouseWheelEvent wheel_event =
	blink::SyntheticWebMouseWheelEventBuilder::Build(
	x, y, x, y, delta_x, delta_y, 0,
	ui::ScrollGranularity::kScrollByPrecisePixel);
	wheel_event.phase = blink::WebMouseWheelEvent::kPhaseBegan;
	GetRouter()->RouteMouseWheelEvent(GetRootView(), &wheel_event,
	ui::LatencyInfo());

	// Runs until we get the UpdateMsgAck callback.
	EXPECT_EQ(blink::mojom::InputEventResultState::kConsumed,
	update_msg_watcher->WaitForAck());

	EXPECT_EQ(0, EvalJs(shell(), "document.scrollingElement.scrollTop"));
	EXPECT_EQ(0, EvalJs(shell(), "documentWheelEventCounter"));
	EXPECT_EQ(1, EvalJs(shell(), "scrollableDivWheelEventCounter"));

	// Remove the scrollableDiv which is the current target for wheel events.
	EXPECT_TRUE(
	ExecJs(shell(), "scrollableDiv.parentNode.removeChild(scrollableDiv)"));

	wheel_event.phase = blink::WebMouseWheelEvent::kPhaseChanged;
	GetRouter()->RouteMouseWheelEvent(GetRootView(), &wheel_event,
	ui::LatencyInfo());

	// Runs until we get the UpdateMsgAck callbacks.
	EXPECT_EQ(blink::mojom::InputEventResultState::kConsumed,
	update_msg_watcher->WaitForAck());

	// Wait for the document event listenr to handle the second wheel event.
	while (EvalJs(shell(), "documentWheelEventCounter") != 1) {
	GiveItSomeTime();
	}

	EXPECT_EQ(1, EvalJs(shell(), "scrollableDivWheelEventCounter"));
	}

	// crbug.com/777258 Flaky everywhere.
	IN_PROC_BROWSER_TEST_F(
	WheelScrollLatchingBrowserTest,
	DISABLED_WheelScrollingRelatchWhenLatchedScrollerRemoved) {
	LoadURL(kWheelEventLatchingDataURL);
	EXPECT_EQ(EvalJs(shell(), "document.scrollingElement.scrollTop"), 0);
	EXPECT_EQ(EvalJs(shell(), "scrollableDiv.scrollTop"), 0);
	float x = (EvalJs(shell(), "scrollableDiv.getBoundingClientRect().left")
	.ExtractDouble() +
	EvalJs(shell(), "scrollableDiv.getBoundingClientRect().right")
	.ExtractDouble()) /
	2;
	float y = (EvalJs(shell(), "scrollableDiv.getBoundingClientRect().top")
	.ExtractDouble() +
	EvalJs(shell(), "scrollableDiv.getBoundingClientRect().bottom")
	.ExtractDouble()) /
	2;
	#if BUILDFLAG(IS_CHROMEOS)
	bool precise = true;
	#else
	bool precise = false;
	#endif
	// Send a GSB event to start scrolling the scrollableDiv.
	blink::WebGestureEvent gesture_scroll_begin(
	blink::WebGestureEvent::Type::kGestureScrollBegin,
	blink::WebInputEvent::kNoModifiers,
	blink::WebInputEvent::GetStaticTimeStampForTests(),
	blink::WebGestureDevice::kTouchpad);
	gesture_scroll_begin.data.scroll_begin.delta_hint_units =
	precise ? ui::ScrollGranularity::kScrollByPrecisePixel
	: ui::ScrollGranularity::kScrollByPixel;
	gesture_scroll_begin.data.scroll_begin.delta_x_hint = 0.f;
	gesture_scroll_begin.data.scroll_begin.delta_y_hint = -20.f;
	gesture_scroll_begin.SetPositionInWidget(gfx::PointF(x, y));
	gesture_scroll_begin.SetPositionInScreen(gfx::PointF(x, y));
	GetRootView()->ProcessGestureEvent(gesture_scroll_begin, ui::LatencyInfo());

	// Send the first GSU event.
	blink::WebGestureEvent gesture_scroll_update(gesture_scroll_begin);
	gesture_scroll_update.SetType(
	blink::WebGestureEvent::Type::kGestureScrollUpdate);
	gesture_scroll_update.data.scroll_update.delta_units =
	precise ? ui::ScrollGranularity::kScrollByPrecisePixel
	: ui::ScrollGranularity::kScrollByPixel;
	gesture_scroll_update.data.scroll_update.delta_x = 0.f;
	gesture_scroll_update.data.scroll_update.delta_y = -20.f;
	GetRootView()->ProcessGestureEvent(gesture_scroll_update, ui::LatencyInfo());

	// Wait for the scrollableDiv to scroll.
	while (EvalJs(shell(), "scrollableDiv.scrollTop") < 20) {
	GiveItSomeTime();
	}

	// Remove the scrollableDiv which is the current scroller and send the second
	// GSU.
	EXPECT_TRUE(
	ExecJs(shell(), "scrollableDiv.parentNode.removeChild(scrollableDiv)"));
	GiveItSomeTime();
	GetRootView()->ProcessGestureEvent(gesture_scroll_update, ui::LatencyInfo());
	while (EvalJs(shell(), "document.scrollingElement.scrollTop") < 20) {
	GiveItSomeTime();
	}
	}

	const char kWheelRetargetIfPreventedByDefault[] = R"HTML(
	<!DOCTYPE html>
	<meta name='viewport' content='width=device-width, minimum-scale=1'>
	<style>
	%23blueDiv {
	position: absolute;
	left: 50px;
	top: 100px;
	width: 200px;
	height: 200px;
	display: block;
	background: blue;
	}
	%23redDiv {
	width: 200px;
	height: 200px;
	display: none;
	background: red;
	}
	</style>
	<body>
	<div id='blueDiv'>
	<div id='redDiv'></div>
	</div>
	</body>
	<script>
	var blueDiv = document.getElementById('blueDiv');
	var redDiv = document.getElementById('redDiv');
	var domTarget = 'noTarget';
	var x = (blueDiv.getBoundingClientRect().left +
	blueDiv.getBoundingClientRect().right) / 2;
	var y = (blueDiv.getBoundingClientRect().top +
	blueDiv.getBoundingClientRect().bottom) /2;
	blueDiv.addEventListener('wheel', function(e) {
	e.preventDefault();
	domTarget = 'blueDiv';
	redDiv.style.display = 'block';
	});
	redDiv.addEventListener('wheel', function(e) {
	domTarget = 'redDiv';
	e.stopPropagation();
	});
	</script>)HTML";

	IN_PROC_BROWSER_TEST_F(WheelScrollLatchingBrowserTest,
	WheelEventRetargetOnPreventDefault) {
	LoadURL(kWheelRetargetIfPreventedByDefault);

	float x = EvalJs(shell(), "x").ExtractDouble();
	float y = EvalJs(shell(), "y").ExtractDouble();

	// Send the first wheel event.
	auto wheel_msg_watcher = std::make_unique<InputMsgWatcher>(
	GetWidgetHost(), blink::WebInputEvent::Type::kMouseWheel);
	blink::WebMouseWheelEvent wheel_event =
	blink::SyntheticWebMouseWheelEventBuilder::Build(
	x, y, x, y, 1, 1, 0, ui::ScrollGranularity::kScrollByPrecisePixel);
	wheel_event.phase = blink::WebMouseWheelEvent::kPhaseBegan;
	GetRouter()->RouteMouseWheelEvent(GetRootView(), &wheel_event,
	ui::LatencyInfo());

	// Run until we get the callback, then check the target.
	EXPECT_EQ(blink::mojom::InputEventResultState::kConsumed,
	wheel_msg_watcher->WaitForAck());
	EXPECT_EQ("blueDiv", EvalJs(shell(), "domTarget"));

	// Send the second wheel event.
	wheel_msg_watcher = std::make_unique<InputMsgWatcher>(
	GetWidgetHost(), blink::WebInputEvent::Type::kMouseWheel);
	wheel_event.phase = blink::WebMouseWheelEvent::kPhaseChanged;
	GetRouter()->RouteMouseWheelEvent(GetRootView(), &wheel_event,
	ui::LatencyInfo());

	// Run until we get the callback, then check the target.
	EXPECT_EQ(blink::mojom::InputEventResultState::kNotConsumed,
	wheel_msg_watcher->WaitForAck());
	EXPECT_EQ("redDiv", EvalJs(shell(), "domTarget"));
	}

	} // namespace content