Fieldset NG: Support position:sticky content
LayoutBoxModelObject::UpdateStickyPositionConstraints() should allow an
anonymous fieldset content box as a sticky container.
Bug: 1128479, 1146925, 1149320
Change-Id: I12e37e347fcb4300891f524f0a2b7256d0d23d78
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2562000
Reviewed-by: Xianzhu Wang <wangxianzhu@chromium.org>
Commit-Queue: Kent Tamura <tkent@chromium.org>
Cr-Commit-Position: refs/heads/master@{#831727}
diff --git a/third_party/blink/renderer/core/css/resolver/style_adjuster.cc b/third_party/blink/renderer/core/css/resolver/style_adjuster.cc
index 53c5ca1..ed4f80eb 100644
--- a/third_party/blink/renderer/core/css/resolver/style_adjuster.cc
+++ b/third_party/blink/renderer/core/css/resolver/style_adjuster.cc
@@ -44,7 +44,6 @@
#include "third_party/blink/renderer/core/frame/local_frame_view.h"
#include "third_party/blink/renderer/core/frame/settings.h"
#include "third_party/blink/renderer/core/frame/web_feature.h"
-#include "third_party/blink/renderer/core/html/forms/html_field_set_element.h"
#include "third_party/blink/renderer/core/html/forms/html_input_element.h"
#include "third_party/blink/renderer/core/html/forms/html_text_area_element.h"
#include "third_party/blink/renderer/core/html/html_iframe_element.h"
@@ -699,20 +698,6 @@
AdjustStyleForDisplay(style, layout_parent_style, element,
element ? &element->GetDocument() : nullptr);
- // TOOD(crbug.com/1146925): Sticky content in a scrollable FIELDSET triggers
- // a DHCECK failure in |StickyPositionScrollingConstraints::
- // AncestorContainingBlockOffset()|. We disable it until the root cause is
- // fixed.
- if (style.GetPosition() == EPosition::kSticky && element) {
- for (const Node& ancestor : FlatTreeTraversal::AncestorsOf(*element)) {
- if (const auto* fieldset = DynamicTo<HTMLFieldSetElement>(ancestor)) {
- if (!fieldset->ComputedStyleRef().IsOverflowVisibleAlongBothAxes())
- style.SetPosition(EPosition::kStatic);
- break;
- }
- }
- }
-
// If this is a child of a LayoutNGCustom, we need the name of the parent
// layout function for invalidation purposes.
if (layout_parent_style.IsDisplayLayoutCustomBox()) {
diff --git a/third_party/blink/renderer/core/layout/layout_box_model_object.cc b/third_party/blink/renderer/core/layout/layout_box_model_object.cc
index eec78a97..3517624c 100644
--- a/third_party/blink/renderer/core/layout/layout_box_model_object.cc
+++ b/third_party/blink/renderer/core/layout/layout_box_model_object.cc
@@ -963,8 +963,11 @@
// The location container for boxes is not always the containing block.
LayoutObject* location_container =
IsLayoutInline() ? Container() : To<LayoutBox>(this)->LocationContainer();
- // Skip anonymous containing blocks.
+ // Skip anonymous containing blocks except for anonymous fieldset content box.
while (sticky_container->IsAnonymous()) {
+ if (sticky_container->Parent() &&
+ sticky_container->Parent()->IsLayoutNGFieldset())
+ break;
sticky_container = sticky_container->ContainingBlock();
}
diff --git a/third_party/blink/web_tests/external/wpt/html/rendering/non-replaced-elements/the-fieldset-and-legend-elements/sticky-content-ref.html b/third_party/blink/web_tests/external/wpt/html/rendering/non-replaced-elements/the-fieldset-and-legend-elements/sticky-content-ref.html
new file mode 100644
index 0000000..95e3c05
--- /dev/null
+++ b/third_party/blink/web_tests/external/wpt/html/rendering/non-replaced-elements/the-fieldset-and-legend-elements/sticky-content-ref.html
@@ -0,0 +1,34 @@
+<!DOCTYPE html>
+<body>
+<style>
+body {
+ margin: 0;
+}
+
+.fieldset div {
+ height:1000px;
+}
+
+span {
+ background: lime;
+ display: block;
+ height: 40px;
+ position: absolute;
+ top: 4px;
+ left: 0px;
+ width: 40px;
+}
+
+.fieldset {
+ border: none;
+ height: 400px;
+ margin: 0;
+ overflow: scroll;
+ padding: 0;
+}
+</style>
+<div class="fieldset"><div><span></span></div></div>
+<script>
+document.querySelector('.fieldset').scrollTop = 1000;
+</script>
+</body>
diff --git a/third_party/blink/web_tests/external/wpt/html/rendering/non-replaced-elements/the-fieldset-and-legend-elements/sticky-content.html b/third_party/blink/web_tests/external/wpt/html/rendering/non-replaced-elements/the-fieldset-and-legend-elements/sticky-content.html
new file mode 100644
index 0000000..f60d9ec
--- /dev/null
+++ b/third_party/blink/web_tests/external/wpt/html/rendering/non-replaced-elements/the-fieldset-and-legend-elements/sticky-content.html
@@ -0,0 +1,35 @@
+<!DOCTYPE html>
+<link rel="help" href="http://crbug.com/1146925">
+<link rel="match" href="sticky-content-ref.html">
+<body>
+<style>
+body {
+ margin: 0;
+}
+
+fieldset div {
+ height:1000px;
+}
+
+span {
+ background: lime;
+ display: block;
+ height: 40px;
+ position: sticky;
+ top: 4px;
+ width: 40px;
+}
+
+fieldset {
+ border: none;
+ height: 400px;
+ margin: 0;
+ overflow: scroll;
+ padding: 0;
+}
+</style>
+<fieldset><div><span></span></div></fieldset>
+<script>
+document.querySelector('fieldset').scrollTop = 1000;
+</script>
+</body>
