Handle nested position:sticky elements correctly (compositor)

third_party/WebKit/Source/core/layout/compositing/CompositingReasonFinderTest.cpp

 // Copyright 2016 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/layout/compositing/CompositingReasonFinder.h"
 
 #include "core/frame/FrameView.h"
 #include "core/layout/LayoutBlock.h"
 #include "core/layout/LayoutTestHelper.h"
 #include "core/paint/PaintLayer.h"
@@ skipping 253 matching lines @@
   EXPECT_TRUE(
       CompositingReasonFinder::requiresCompositingForEffectAnimation(*style));
 
   style->setIsRunningOpacityAnimationOnCompositor(false);
   style->setIsRunningFilterAnimationOnCompositor(false);
   style->setIsRunningBackdropFilterAnimationOnCompositor(true);
   EXPECT_TRUE(
       CompositingReasonFinder::requiresCompositingForEffectAnimation(*style));
 }
 
-TEST_F(CompositingReasonFinderTest, DoNotCompositeNestedSticky) {
-  ScopedCompositeFixedPositionForTest compositeFixedPosition(true);
-
-  setBodyInnerHTML(
-      "<style>.scroller { overflow: scroll; height: 200px; width: 100px; }"
-      ".container { height: 500px; }"
-      ".opaque { background-color: white; contain: paint; }"
-      "#outerSticky { height: 50px; position: sticky; top: 0px; }"
-      "#innerSticky { height: 20px; position: sticky; top: 25px; }</style>"
-      "<div class='scroller'>"
-      "  <div class='container'>"
-      "    <div id='outerSticky' class='opaque'>"
-      "      <div id='innerSticky' class='opaque'></div>"
-      "    </div>"
-      "  </div>"
-      "</div>");
-  document().view()->updateAllLifecyclePhases();
-
-  Element* outerSticky = document().getElementById("outerSticky");
-  PaintLayer* outerStickyLayer =
-      toLayoutBoxModelObject(outerSticky->layoutObject())->layer();
-  ASSERT_TRUE(outerStickyLayer);
-
-  Element* innerSticky = document().getElementById("innerSticky");
-  PaintLayer* innerStickyLayer =
-      toLayoutBoxModelObject(innerSticky->layoutObject())->layer();
-  ASSERT_TRUE(innerStickyLayer);
-
-  EXPECT_EQ(PaintsIntoOwnBacking, outerStickyLayer->compositingState());
-  EXPECT_EQ(NotComposited, innerStickyLayer->compositingState());
-}
-
 }  // namespace blink