Clean compositing inputs for location APIs for sticky-affected elements.

third_party/WebKit/Source/core/paint/PaintLayerScrollableAreaTest.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/paint/PaintLayerScrollableArea.h"
 
 #include "core/frame/FrameView.h"
 #include "core/layout/LayoutBoxModelObject.h"
 #include "core/layout/LayoutTestHelper.h"
 #include "core/paint/PaintLayer.h"
@@ skipping 11 matching lines @@
 class MockChromeClient : public EmptyChromeClient {
  public:
   MOCK_METHOD3(MockSetToolTip, void(LocalFrame*, const String&, TextDirection));
   void SetToolTip(LocalFrame& frame,
                   const String& tooltip_text,
                   TextDirection dir) override {
     MockSetToolTip(&frame, tooltip_text, dir);
   }
 };
 
-}  // namespace {
+}  // namespace
 
 class PaintLayerScrollableAreaTest : public RenderingTest {
  public:
   PaintLayerScrollableAreaTest()
       : RenderingTest(EmptyLocalFrameClient::Create()),
         chrome_client_(new MockChromeClient) {}
 
   ~PaintLayerScrollableAreaTest() {
     testing::Mock::VerifyAndClearExpectations(&GetChromeClient());
   }
@@ skipping 578 matching lines @@
       "  </div>"
       "</div>");
   GetDocument().View()->UpdateAllLifecyclePhases();
   Element* container = GetDocument().GetElementById("container");
   ASSERT_TRUE(container);
   PaintLayerScrollableArea* scrollable_area =
       ToLayoutBoxModelObject(container->GetLayoutObject())->GetScrollableArea();
   ASSERT_TRUE(scrollable_area);
   EXPECT_FALSE(scrollable_area->HasHorizontalScrollbar());
 }
+
+TEST_F(PaintLayerScrollableAreaTest,
+       StickyPositionConstraintsInvalidatedByLayout) {
+  SetBodyInnerHTML(
+      "<style>#scroller { overflow-y: scroll; height: 100px; }"
+      "#sticky { height: 25px; position: sticky; top: 0; }"
+      "#padding { height: 500px; }</style>"
+      "<div id='scroller'><div id='sticky'></div><div id='padding'></div>"
+      "</div>");
+
+  LayoutBoxModelObject* scroller =
+      ToLayoutBoxModelObject(GetLayoutObjectByElementId("scroller"));
+  LayoutBoxModelObject* sticky =
+      ToLayoutBoxModelObject(GetLayoutObjectByElementId("sticky"));
+
+  EXPECT_FALSE(sticky->Layer()->NeedsCompositingInputsUpdate());
+
+  PaintLayerScrollableArea* scrollable_area = scroller->GetScrollableArea();
+  ASSERT_TRUE(scrollable_area);
+
+  // Fake layout.
+  scrollable_area->UpdateAfterLayout();
+
+  EXPECT_TRUE(sticky->Layer()->NeedsCompositingInputsUpdate());
+  EXPECT_EQ(0u, scrollable_area->GetStickyConstraintsMap().size());
 }
+}