third_party/WebKit/Source/web/tests/ScrollMetricsTest.cpp - chromium/src - Git at Google

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

 #include "core/frame/LocalFrameView.h"
 #include "core/frame/WebLocalFrameBase.h"
 #include "core/geometry/DOMRect.h"
 #include "core/input/EventHandler.h"
 #include "core/layout/LayoutView.h"
 #include "core/paint/PaintLayerScrollableArea.h"
 #include "core/testing/sim/SimDisplayItemList.h"
 #include "core/testing/sim/SimRequest.h"
 #include "core/testing/sim/SimTest.h"
 #include "platform/scroll/MainThreadScrollingReason.h"
 #include "platform/scroll/ScrollerSizeMetrics.h"
 #include "platform/testing/HistogramTester.h"
 #include "platform/testing/TestingPlatformSupport.h"
 #include "platform/testing/UnitTestHelpers.h"

 #define EXPECT_WHEEL_BUCKET(reason, count)     \
   histogram_tester.ExpectBucketCount(          \
       "Renderer4.MainThreadWheelScrollReason", \
       GetBucketIndex(MainThreadScrollingReason::reason), count);

 #define EXPECT_TOUCH_BUCKET(reason, count)       \
   histogram_tester.ExpectBucketCount(            \
       "Renderer4.MainThreadGestureScrollReason", \
       GetBucketIndex(MainThreadScrollingReason::reason), count);

 #define EXPECT_WHEEL_TOTAL(count)                                            \
   histogram_tester.ExpectTotalCount("Renderer4.MainThreadWheelScrollReason", \
                                     count);

 #define EXPECT_TOUCH_TOTAL(count)                                              \
   histogram_tester.ExpectTotalCount("Renderer4.MainThreadGestureScrollReason", \
                                     count);

 namespace blink {

 namespace {

 class ScrollMetricsTest : public SimTest {
  public:
   void SetUpHtml(const char*);
   void Scroll(Element*, const WebGestureDevice);
 };

 class NonCompositedMainThreadScrollingReasonRecordTest
     : public ScrollMetricsTest {
  protected:
   int GetBucketIndex(uint32_t reason);
 };

 class ScrollBeginEventBuilder : public WebGestureEvent {
  public:
   ScrollBeginEventBuilder(IntPoint position,
                           FloatPoint delta,
                           WebGestureDevice device)
       : WebGestureEvent() {
     type_ = WebInputEvent::kGestureScrollBegin;
     x = global_x = position.X();
     y = global_y = position.Y();
     data.scroll_begin.delta_y_hint = delta.Y();
     source_device = device;
     frame_scale_ = 1;
   }
 };

 class ScrollUpdateEventBuilder : public WebGestureEvent {
  public:
   ScrollUpdateEventBuilder() : WebGestureEvent() {
     type_ = WebInputEvent::kGestureScrollUpdate;
     data.scroll_update.delta_x = 0.0f;
     data.scroll_update.delta_y = 1.0f;
     data.scroll_update.velocity_x = 0;
     data.scroll_update.velocity_y = 1;
     frame_scale_ = 1;
   }
 };

 class ScrollEndEventBuilder : public WebGestureEvent {
  public:
   ScrollEndEventBuilder() : WebGestureEvent() {
     type_ = WebInputEvent::kGestureScrollEnd;
     frame_scale_ = 1;
   }
 };

 int NonCompositedMainThreadScrollingReasonRecordTest::GetBucketIndex(
     uint32_t reason) {
   int index = 1;
   while (!(reason & 1)) {
     reason >>= 1;
     ++index;
   }
   DCHECK_EQ(reason, 1u);
   return index;
 }

 void ScrollMetricsTest::Scroll(Element* element,
                                const WebGestureDevice device) {
   DCHECK(element);
   DCHECK(element->getBoundingClientRect());
   DOMRect* rect = element->getBoundingClientRect();
   ScrollBeginEventBuilder scroll_begin(
       IntPoint(rect->left() + rect->width() / 2,
                rect->top() + rect->height() / 2),
       FloatPoint(0.f, 1.f), device);
   ScrollUpdateEventBuilder scroll_update;
   ScrollEndEventBuilder scroll_end;
   GetDocument().GetFrame()->GetEventHandler().HandleGestureEvent(scroll_begin);
   GetDocument().GetFrame()->GetEventHandler().HandleGestureEvent(scroll_update);
   GetDocument().GetFrame()->GetEventHandler().HandleGestureEvent(scroll_end);
   ASSERT_GT(scroll_update.DeltaYInRootFrame(), 0);
 }

 void ScrollMetricsTest::SetUpHtml(const char* html_content) {
   WebView().Resize(WebSize(800, 600));
   SimRequest request("https://example.com/test.html", "text/html");
   LoadURL("https://example.com/test.html");
   request.Complete(html_content);
   Compositor().BeginFrame();
 }

 TEST_F(ScrollMetricsTest, ScrollerSizeOnPageLoadHistogramRecordingTest) {
   HistogramTester histogram_tester;
   SetUpHtml(
       "<!DOCTYPE html>"
       "<style>"
       " .smallBox { overflow: scroll; width: 100px; height: 100px; }"
       " .largeBox { overflow: auto; width: 500px; height: 500px; }"
       " .nonScrollableBox { overflow: auto; width: 200px; height: 200px; }"
       " .spacer { height: 1000px; }"
       " body { height: 2000px; width: 1000px; }"
       "</style>"
       "<div class='smallBox'><div class='spacer'></div></div>"
       "<div class='largeBox'><div class='spacer'></div></div>"
       "<div class='notScrollableBox'></div>"
       "<div style='width: 300px; height: 300px;'>"
       " <div class='spacer'></div>"
       "</div>");

   testing::RunPendingTasks();

   // SmallBox added to count.
   histogram_tester.ExpectBucketCount("Event.Scroll.ScrollerSize.OnLoad", 10000,
                                      1);
   // LargeBox added to count.
   histogram_tester.ExpectBucketCount("Event.Scroll.ScrollerSize.OnLoad",
                                      kScrollerSizeLargestBucket, 1);

   // Non-scrollable box is not added to count.
   histogram_tester.ExpectBucketCount("Event.Scroll.ScrollerSize.OnLoad", 40000,
                                      0);

   // The fourth div without "overflow: scroll" is not supposed to be added to
   // count.
   histogram_tester.ExpectBucketCount("Event.Scroll.ScrollerSize.OnLoad", 90000,
                                      0);
   // Root scroller is not added to count.
   histogram_tester.ExpectBucketCount("Event.Scroll.ScrollerSize.OnLoad",
                                      kScrollerSizeLargestBucket, 1);
   histogram_tester.ExpectTotalCount("Event.Scroll.ScrollerSize.OnLoad", 2);
 }

 TEST_F(ScrollMetricsTest,
        ScrollerSizeOfMainThreadScrollingHistogramRecordingTest) {
   HistogramTester histogram_tester;
   SetUpHtml(
       "<!DOCTYPE html>"
       "<style>"
       " .container { width: 200px; height: 200px; overflow: scroll; }"
       " .box { width: 100px; height: 100px; overflow: scroll; }"
       " .spacer { height: 1000px; }"
       " .target { width: 200px; height: 200px; }"
       " body { height: 2000px; }"
       "</style>"
       "<div class='container'>"
       " <div id='box' class='box'>"
       "  <div id='content' class='spacer'></div>"
       " </div>"
       "</div>"
       "<div id='target' class='target'></div>");

   Element* box = GetDocument().getElementById("box");

   // Test wheel scroll on the box.
   Scroll(box, kWebGestureDeviceTouchpad);
   histogram_tester.ExpectBucketCount("Event.Scroll.ScrollerSize.OnScroll_Wheel",
                                      10000, 1);
   // Only the first scrollable area is recorded.
   histogram_tester.ExpectBucketCount("Event.Scroll.ScrollerSize.OnScroll_Wheel",
                                      40000, 0);
   histogram_tester.ExpectTotalCount("Event.Scroll.ScrollerSize.OnScroll_Wheel",
                                     1);

   // Test touch scroll.
   Scroll(box, kWebGestureDeviceTouchscreen);
   histogram_tester.ExpectBucketCount("Event.Scroll.ScrollerSize.OnScroll_Touch",
                                      10000, 1);
   histogram_tester.ExpectTotalCount("Event.Scroll.ScrollerSize.OnScroll_Touch",
                                     1);

   // Scrolling the non-scrollable target leads to scroll the root layer which
   // doesn't add to count.
   Element* body_scroll_target = GetDocument().getElementById("target");
   Scroll(body_scroll_target, kWebGestureDeviceTouchscreen);
   histogram_tester.ExpectBucketCount("Event.Scroll.ScrollerSize.OnScroll_Touch",
                                      kScrollerSizeLargestBucket, 0);
   histogram_tester.ExpectTotalCount("Event.Scroll.ScrollerSize.OnScroll_Touch",
                                     1);
 }

 TEST_F(NonCompositedMainThreadScrollingReasonRecordTest,
        TouchAndWheelGeneralTest) {
   SetUpHtml(
       "<style>"
       " .box { overflow:scroll; width: 100px; height: 100px; }"
       " .translucent { opacity: 0.5; }"
       " .spacer { height: 1000px; }"
       "</style>"
       "<div id='box' class='translucent box'>"
       " <div class='spacer'></div>"
       "</div>");

   GetDocument().View()->UpdateAllLifecyclePhases();

   Element* box = GetDocument().getElementById("box");
   HistogramTester histogram_tester;

   // Test touch scroll.
   Scroll(box, kWebGestureDeviceTouchscreen);
   EXPECT_TOUCH_BUCKET(kHasOpacityAndLCDText, 1);
   EXPECT_TOUCH_BUCKET(kBackgroundNotOpaqueInRectAndLCDText, 1);

   Scroll(box, kWebGestureDeviceTouchscreen);
   EXPECT_TOUCH_BUCKET(kHasOpacityAndLCDText, 2);
   EXPECT_TOUCH_BUCKET(kBackgroundNotOpaqueInRectAndLCDText, 2);
   EXPECT_TOUCH_TOTAL(4);

   // Test wheel scroll.
   Scroll(box, kWebGestureDeviceTouchpad);
   EXPECT_WHEEL_BUCKET(kHasOpacityAndLCDText, 1);
   EXPECT_WHEEL_BUCKET(kBackgroundNotOpaqueInRectAndLCDText, 1);
   EXPECT_WHEEL_TOTAL(2);
 }

 TEST_F(NonCompositedMainThreadScrollingReasonRecordTest,
        CompositedScrollableAreaTest) {
   SetUpHtml(
       "<style>"
       " .box { overflow:scroll; width: 100px; height: 100px; }"
       " .translucent { opacity: 0.5; }"
       " .composited { will-change: transform; }"
       " .spacer { height: 1000px; }"
       "</style>"
       "<div id='box' class='translucent box'>"
       " <div class='spacer'></div>"
       "</div>");

   WebView().GetSettings()->SetAcceleratedCompositingEnabled(true);
   GetDocument().View()->SetParentVisible(true);
   GetDocument().View()->SetSelfVisible(true);
   GetDocument().View()->UpdateAllLifecyclePhases();

   Element* box = GetDocument().getElementById("box");
   HistogramTester histogram_tester;

   Scroll(box, kWebGestureDeviceTouchpad);
   EXPECT_WHEEL_BUCKET(kHasOpacityAndLCDText, 1);
   EXPECT_WHEEL_BUCKET(kBackgroundNotOpaqueInRectAndLCDText, 1);
   EXPECT_WHEEL_TOTAL(2);

   box->setAttribute("class", "composited translucent box");
   GetDocument().View()->UpdateAllLifecyclePhases();
   Scroll(box, kWebGestureDeviceTouchpad);
   EXPECT_FALSE(ToLayoutBox(box->GetLayoutObject())
                    ->GetScrollableArea()
                    ->GetNonCompositedMainThreadScrollingReasons());
   EXPECT_WHEEL_BUCKET(kHasOpacityAndLCDText, 1);
   EXPECT_WHEEL_BUCKET(kBackgroundNotOpaqueInRectAndLCDText, 1);
   EXPECT_WHEEL_TOTAL(2);
 }

 TEST_F(NonCompositedMainThreadScrollingReasonRecordTest,
        NotScrollableAreaTest) {
   SetUpHtml(
       "<style>.box { overflow:scroll; width: 100px; height: 100px; }"
       " .translucent { opacity: 0.5; }"
       " .hidden { overflow: hidden; }"
       " .spacer { height: 1000px; }"
       "</style>"
       "<div id='box' class='translucent box'>"
       " <div class='spacer'></div>"
       "</div>");

   GetDocument().View()->UpdateAllLifecyclePhases();

   Element* box = GetDocument().getElementById("box");
   HistogramTester histogram_tester;

   Scroll(box, kWebGestureDeviceTouchpad);
   EXPECT_WHEEL_BUCKET(kHasOpacityAndLCDText, 1);
   EXPECT_WHEEL_BUCKET(kBackgroundNotOpaqueInRectAndLCDText, 1);
   EXPECT_WHEEL_TOTAL(2);

   box->setAttribute("class", "hidden translucent box");
   GetDocument().View()->UpdateAllLifecyclePhases();
   Scroll(box, kWebGestureDeviceTouchpad);
   EXPECT_WHEEL_BUCKET(kHasOpacityAndLCDText, 1);
   EXPECT_WHEEL_BUCKET(kBackgroundNotOpaqueInRectAndLCDText, 1);
   EXPECT_WHEEL_TOTAL(2);
 }

 TEST_F(NonCompositedMainThreadScrollingReasonRecordTest, NestedScrollersTest) {
   SetUpHtml(
       "<style>"
       " .container { overflow:scroll; width: 200px; height: 200px; }"
       " .box { overflow:scroll; width: 100px; height: 100px; }"
       " .translucent { opacity: 0.5; }"
       " .transform { transform: scale(0.8); }"
       " .with-border-radius { border: 5px solid; border-radius: 5px; }"
       " .spacer { height: 1000px; }"
       " .composited { will-change: transform; }"
       "</style>"
       "<div id='container' class='container with-border-radius'>"
       "  <div class='translucent box'>"
       "    <div id='inner' class='composited transform box'>"
       "      <div class='spacer'></div>"
       "    </div>"
       "    <div class='spacer'></div>"
       "  </div>"
       "  <div class='spacer'></div>"
       "</div>");

   WebView().GetSettings()->SetAcceleratedCompositingEnabled(true);
   GetDocument().View()->SetParentVisible(true);
   GetDocument().View()->SetSelfVisible(true);
   GetDocument().View()->UpdateAllLifecyclePhases();

   Element* box = GetDocument().getElementById("inner");
   HistogramTester histogram_tester;

   Scroll(box, kWebGestureDeviceTouchpad);
   // Scrolling the inner box will gather reasons from the scrolling chain. The
   // inner box itself has no reason because it's composited. Other scrollable
   // areas from the chain have corresponding reasons.
   EXPECT_WHEEL_BUCKET(kHasOpacityAndLCDText, 1);
   EXPECT_WHEEL_BUCKET(kBackgroundNotOpaqueInRectAndLCDText, 1);
   EXPECT_WHEEL_BUCKET(kIsNotStackingContextAndLCDText, 1);
   EXPECT_WHEEL_BUCKET(kHasBorderRadius, 1);
   EXPECT_WHEEL_BUCKET(kHasTransformAndLCDText, 0);
   EXPECT_WHEEL_TOTAL(4);
 }

 }  // namespace

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

	#include "core/frame/LocalFrameView.h"
	#include "core/frame/WebLocalFrameBase.h"
	#include "core/geometry/DOMRect.h"
	#include "core/input/EventHandler.h"
	#include "core/layout/LayoutView.h"
	#include "core/paint/PaintLayerScrollableArea.h"
	#include "core/testing/sim/SimDisplayItemList.h"
	#include "core/testing/sim/SimRequest.h"
	#include "core/testing/sim/SimTest.h"
	#include "platform/scroll/MainThreadScrollingReason.h"
	#include "platform/scroll/ScrollerSizeMetrics.h"
	#include "platform/testing/HistogramTester.h"
	#include "platform/testing/TestingPlatformSupport.h"
	#include "platform/testing/UnitTestHelpers.h"

	#define EXPECT_WHEEL_BUCKET(reason, count) \
	histogram_tester.ExpectBucketCount( \
	"Renderer4.MainThreadWheelScrollReason", \
	GetBucketIndex(MainThreadScrollingReason::reason), count);

	#define EXPECT_TOUCH_BUCKET(reason, count) \
	histogram_tester.ExpectBucketCount( \
	"Renderer4.MainThreadGestureScrollReason", \
	GetBucketIndex(MainThreadScrollingReason::reason), count);

	#define EXPECT_WHEEL_TOTAL(count) \
	histogram_tester.ExpectTotalCount("Renderer4.MainThreadWheelScrollReason", \
	count);

	#define EXPECT_TOUCH_TOTAL(count) \
	histogram_tester.ExpectTotalCount("Renderer4.MainThreadGestureScrollReason", \
	count);

	namespace blink {

	namespace {

	class ScrollMetricsTest : public SimTest {
	public:
	void SetUpHtml(const char*);
	void Scroll(Element*, const WebGestureDevice);
	};

	class NonCompositedMainThreadScrollingReasonRecordTest
	: public ScrollMetricsTest {
	protected:
	int GetBucketIndex(uint32_t reason);
	};

	class ScrollBeginEventBuilder : public WebGestureEvent {
	public:
	ScrollBeginEventBuilder(IntPoint position,
	FloatPoint delta,
	WebGestureDevice device)
	: WebGestureEvent() {
	type_ = WebInputEvent::kGestureScrollBegin;
	x = global_x = position.X();
	y = global_y = position.Y();
	data.scroll_begin.delta_y_hint = delta.Y();
	source_device = device;
	frame_scale_ = 1;
	}
	};

	class ScrollUpdateEventBuilder : public WebGestureEvent {
	public:
	ScrollUpdateEventBuilder() : WebGestureEvent() {
	type_ = WebInputEvent::kGestureScrollUpdate;
	data.scroll_update.delta_x = 0.0f;
	data.scroll_update.delta_y = 1.0f;
	data.scroll_update.velocity_x = 0;
	data.scroll_update.velocity_y = 1;
	frame_scale_ = 1;
	}
	};

	class ScrollEndEventBuilder : public WebGestureEvent {
	public:
	ScrollEndEventBuilder() : WebGestureEvent() {
	type_ = WebInputEvent::kGestureScrollEnd;
	frame_scale_ = 1;
	}
	};

	int NonCompositedMainThreadScrollingReasonRecordTest::GetBucketIndex(
	uint32_t reason) {
	int index = 1;
	while (!(reason & 1)) {
	reason >>= 1;
	++index;
	}
	DCHECK_EQ(reason, 1u);
	return index;
	}

	void ScrollMetricsTest::Scroll(Element* element,
	const WebGestureDevice device) {
	DCHECK(element);
	DCHECK(element->getBoundingClientRect());
	DOMRect* rect = element->getBoundingClientRect();
	ScrollBeginEventBuilder scroll_begin(
	IntPoint(rect->left() + rect->width() / 2,
	rect->top() + rect->height() / 2),
	FloatPoint(0.f, 1.f), device);
	ScrollUpdateEventBuilder scroll_update;
	ScrollEndEventBuilder scroll_end;
	GetDocument().GetFrame()->GetEventHandler().HandleGestureEvent(scroll_begin);
	GetDocument().GetFrame()->GetEventHandler().HandleGestureEvent(scroll_update);
	GetDocument().GetFrame()->GetEventHandler().HandleGestureEvent(scroll_end);
	ASSERT_GT(scroll_update.DeltaYInRootFrame(), 0);
	}

	void ScrollMetricsTest::SetUpHtml(const char* html_content) {
	WebView().Resize(WebSize(800, 600));
	SimRequest request("https://example.com/test.html", "text/html");
	LoadURL("https://example.com/test.html");
	request.Complete(html_content);
	Compositor().BeginFrame();
	}

	TEST_F(ScrollMetricsTest, ScrollerSizeOnPageLoadHistogramRecordingTest) {
	HistogramTester histogram_tester;
	SetUpHtml(
	"<!DOCTYPE html>"
	"<style>"
	" .smallBox { overflow: scroll; width: 100px; height: 100px; }"
	" .largeBox { overflow: auto; width: 500px; height: 500px; }"
	" .nonScrollableBox { overflow: auto; width: 200px; height: 200px; }"
	" .spacer { height: 1000px; }"
	" body { height: 2000px; width: 1000px; }"
	"</style>"
	"<div class='smallBox'><div class='spacer'></div></div>"
	"<div class='largeBox'><div class='spacer'></div></div>"
	"<div class='notScrollableBox'></div>"
	"<div style='width: 300px; height: 300px;'>"
	" <div class='spacer'></div>"
	"</div>");

	testing::RunPendingTasks();

	// SmallBox added to count.
	histogram_tester.ExpectBucketCount("Event.Scroll.ScrollerSize.OnLoad", 10000,
	1);
	// LargeBox added to count.
	histogram_tester.ExpectBucketCount("Event.Scroll.ScrollerSize.OnLoad",
	kScrollerSizeLargestBucket, 1);

	// Non-scrollable box is not added to count.
	histogram_tester.ExpectBucketCount("Event.Scroll.ScrollerSize.OnLoad", 40000,
	0);

	// The fourth div without "overflow: scroll" is not supposed to be added to
	// count.
	histogram_tester.ExpectBucketCount("Event.Scroll.ScrollerSize.OnLoad", 90000,
	0);
	// Root scroller is not added to count.
	histogram_tester.ExpectBucketCount("Event.Scroll.ScrollerSize.OnLoad",
	kScrollerSizeLargestBucket, 1);
	histogram_tester.ExpectTotalCount("Event.Scroll.ScrollerSize.OnLoad", 2);
	}

	TEST_F(ScrollMetricsTest,
	ScrollerSizeOfMainThreadScrollingHistogramRecordingTest) {
	HistogramTester histogram_tester;
	SetUpHtml(
	"<!DOCTYPE html>"
	"<style>"
	" .container { width: 200px; height: 200px; overflow: scroll; }"
	" .box { width: 100px; height: 100px; overflow: scroll; }"
	" .spacer { height: 1000px; }"
	" .target { width: 200px; height: 200px; }"
	" body { height: 2000px; }"
	"</style>"
	"<div class='container'>"
	" <div id='box' class='box'>"
	" <div id='content' class='spacer'></div>"
	" </div>"
	"</div>"
	"<div id='target' class='target'></div>");

	Element* box = GetDocument().getElementById("box");

	// Test wheel scroll on the box.
	Scroll(box, kWebGestureDeviceTouchpad);
	histogram_tester.ExpectBucketCount("Event.Scroll.ScrollerSize.OnScroll_Wheel",
	10000, 1);
	// Only the first scrollable area is recorded.
	histogram_tester.ExpectBucketCount("Event.Scroll.ScrollerSize.OnScroll_Wheel",
	40000, 0);
	histogram_tester.ExpectTotalCount("Event.Scroll.ScrollerSize.OnScroll_Wheel",
	1);

	// Test touch scroll.
	Scroll(box, kWebGestureDeviceTouchscreen);
	histogram_tester.ExpectBucketCount("Event.Scroll.ScrollerSize.OnScroll_Touch",
	10000, 1);
	histogram_tester.ExpectTotalCount("Event.Scroll.ScrollerSize.OnScroll_Touch",
	1);

	// Scrolling the non-scrollable target leads to scroll the root layer which
	// doesn't add to count.
	Element* body_scroll_target = GetDocument().getElementById("target");
	Scroll(body_scroll_target, kWebGestureDeviceTouchscreen);
	histogram_tester.ExpectBucketCount("Event.Scroll.ScrollerSize.OnScroll_Touch",
	kScrollerSizeLargestBucket, 0);
	histogram_tester.ExpectTotalCount("Event.Scroll.ScrollerSize.OnScroll_Touch",
	1);
	}

	TEST_F(NonCompositedMainThreadScrollingReasonRecordTest,
	TouchAndWheelGeneralTest) {
	SetUpHtml(
	"<style>"
	" .box { overflow:scroll; width: 100px; height: 100px; }"
	" .translucent { opacity: 0.5; }"
	" .spacer { height: 1000px; }"
	"</style>"
	"<div id='box' class='translucent box'>"
	" <div class='spacer'></div>"
	"</div>");

	GetDocument().View()->UpdateAllLifecyclePhases();

	Element* box = GetDocument().getElementById("box");
	HistogramTester histogram_tester;

	// Test touch scroll.
	Scroll(box, kWebGestureDeviceTouchscreen);
	EXPECT_TOUCH_BUCKET(kHasOpacityAndLCDText, 1);
	EXPECT_TOUCH_BUCKET(kBackgroundNotOpaqueInRectAndLCDText, 1);

	Scroll(box, kWebGestureDeviceTouchscreen);
	EXPECT_TOUCH_BUCKET(kHasOpacityAndLCDText, 2);
	EXPECT_TOUCH_BUCKET(kBackgroundNotOpaqueInRectAndLCDText, 2);
	EXPECT_TOUCH_TOTAL(4);

	// Test wheel scroll.
	Scroll(box, kWebGestureDeviceTouchpad);
	EXPECT_WHEEL_BUCKET(kHasOpacityAndLCDText, 1);
	EXPECT_WHEEL_BUCKET(kBackgroundNotOpaqueInRectAndLCDText, 1);
	EXPECT_WHEEL_TOTAL(2);
	}

	TEST_F(NonCompositedMainThreadScrollingReasonRecordTest,
	CompositedScrollableAreaTest) {
	SetUpHtml(
	"<style>"
	" .box { overflow:scroll; width: 100px; height: 100px; }"
	" .translucent { opacity: 0.5; }"
	" .composited { will-change: transform; }"
	" .spacer { height: 1000px; }"
	"</style>"
	"<div id='box' class='translucent box'>"
	" <div class='spacer'></div>"
	"</div>");

	WebView().GetSettings()->SetAcceleratedCompositingEnabled(true);
	GetDocument().View()->SetParentVisible(true);
	GetDocument().View()->SetSelfVisible(true);
	GetDocument().View()->UpdateAllLifecyclePhases();

	Element* box = GetDocument().getElementById("box");
	HistogramTester histogram_tester;

	Scroll(box, kWebGestureDeviceTouchpad);
	EXPECT_WHEEL_BUCKET(kHasOpacityAndLCDText, 1);
	EXPECT_WHEEL_BUCKET(kBackgroundNotOpaqueInRectAndLCDText, 1);
	EXPECT_WHEEL_TOTAL(2);

	box->setAttribute("class", "composited translucent box");
	GetDocument().View()->UpdateAllLifecyclePhases();
	Scroll(box, kWebGestureDeviceTouchpad);
	EXPECT_FALSE(ToLayoutBox(box->GetLayoutObject())
	->GetScrollableArea()
	->GetNonCompositedMainThreadScrollingReasons());
	EXPECT_WHEEL_BUCKET(kHasOpacityAndLCDText, 1);
	EXPECT_WHEEL_BUCKET(kBackgroundNotOpaqueInRectAndLCDText, 1);
	EXPECT_WHEEL_TOTAL(2);
	}

	TEST_F(NonCompositedMainThreadScrollingReasonRecordTest,
	NotScrollableAreaTest) {
	SetUpHtml(
	"<style>.box { overflow:scroll; width: 100px; height: 100px; }"
	" .translucent { opacity: 0.5; }"
	" .hidden { overflow: hidden; }"
	" .spacer { height: 1000px; }"
	"</style>"
	"<div id='box' class='translucent box'>"
	" <div class='spacer'></div>"
	"</div>");

	GetDocument().View()->UpdateAllLifecyclePhases();

	Element* box = GetDocument().getElementById("box");
	HistogramTester histogram_tester;

	Scroll(box, kWebGestureDeviceTouchpad);
	EXPECT_WHEEL_BUCKET(kHasOpacityAndLCDText, 1);
	EXPECT_WHEEL_BUCKET(kBackgroundNotOpaqueInRectAndLCDText, 1);
	EXPECT_WHEEL_TOTAL(2);

	box->setAttribute("class", "hidden translucent box");
	GetDocument().View()->UpdateAllLifecyclePhases();
	Scroll(box, kWebGestureDeviceTouchpad);
	EXPECT_WHEEL_BUCKET(kHasOpacityAndLCDText, 1);
	EXPECT_WHEEL_BUCKET(kBackgroundNotOpaqueInRectAndLCDText, 1);
	EXPECT_WHEEL_TOTAL(2);
	}

	TEST_F(NonCompositedMainThreadScrollingReasonRecordTest, NestedScrollersTest) {
	SetUpHtml(
	"<style>"
	" .container { overflow:scroll; width: 200px; height: 200px; }"
	" .box { overflow:scroll; width: 100px; height: 100px; }"
	" .translucent { opacity: 0.5; }"
	" .transform { transform: scale(0.8); }"
	" .with-border-radius { border: 5px solid; border-radius: 5px; }"
	" .spacer { height: 1000px; }"
	" .composited { will-change: transform; }"
	"</style>"
	"<div id='container' class='container with-border-radius'>"
	" <div class='translucent box'>"
	" <div id='inner' class='composited transform box'>"
	" <div class='spacer'></div>"
	" </div>"
	" <div class='spacer'></div>"
	" </div>"
	" <div class='spacer'></div>"
	"</div>");

	WebView().GetSettings()->SetAcceleratedCompositingEnabled(true);
	GetDocument().View()->SetParentVisible(true);
	GetDocument().View()->SetSelfVisible(true);
	GetDocument().View()->UpdateAllLifecyclePhases();

	Element* box = GetDocument().getElementById("inner");
	HistogramTester histogram_tester;

	Scroll(box, kWebGestureDeviceTouchpad);
	// Scrolling the inner box will gather reasons from the scrolling chain. The
	// inner box itself has no reason because it's composited. Other scrollable
	// areas from the chain have corresponding reasons.
	EXPECT_WHEEL_BUCKET(kHasOpacityAndLCDText, 1);
	EXPECT_WHEEL_BUCKET(kBackgroundNotOpaqueInRectAndLCDText, 1);
	EXPECT_WHEEL_BUCKET(kIsNotStackingContextAndLCDText, 1);
	EXPECT_WHEEL_BUCKET(kHasBorderRadius, 1);
	EXPECT_WHEEL_BUCKET(kHasTransformAndLCDText, 0);
	EXPECT_WHEEL_TOTAL(4);
	}

	} // namespace

	} // namespace blink