Compute and include the offset of the sticky box to its enclosing composited layer.

third_party/WebKit/Source/web/tests/ScrollingCoordinatorTest.cpp

 /*
  * Copyright (C) 2012 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
  *     notice, this list of conditions and the following disclaimer in the
@@ skipping 16 matching lines @@
 #include "core/css/CSSStyleSheet.h"
 #include "core/css/StyleSheetList.h"
 #include "core/frame/FrameHost.h"
 #include "core/frame/FrameView.h"
 #include "core/frame/VisualViewport.h"
 #include "core/layout/LayoutPart.h"
 #include "core/layout/api/LayoutViewItem.h"
 #include "core/layout/compositing/CompositedLayerMapping.h"
 #include "core/layout/compositing/PaintLayerCompositor.h"
 #include "core/page/Page.h"
+#include "platform/geometry/IntPoint.h"
+#include "platform/geometry/IntRect.h"
 #include "platform/graphics/GraphicsLayer.h"
 #include "platform/testing/URLTestHelpers.h"
 #include "public/platform/Platform.h"
 #include "public/platform/WebLayer.h"
 #include "public/platform/WebLayerPositionConstraint.h"
 #include "public/platform/WebLayerTreeView.h"
 #include "public/platform/WebURLLoaderMockFactory.h"
 #include "public/web/WebCache.h"
 #include "public/web/WebSettings.h"
 #include "public/web/WebViewClient.h"
@@ skipping 274 matching lines @@
     ASSERT_TRUE(element);
     WebLayer* layer = webLayerFromElement(element);
     ASSERT_TRUE(layer);
     WebLayerPositionConstraint constraint = layer->positionConstraint();
     ASSERT_TRUE(constraint.isFixedPosition);
     ASSERT_TRUE(constraint.isFixedToRightEdge &&
                 constraint.isFixedToBottomEdge);
   }
 }
 
+TEST_F(ScrollingCoordinatorTest, fastScrollingForStickyPosition) {
+  registerMockedHttpURLLoad("sticky-position.html");

[ajuma, 2016/10/07 21:14:42]

Did you forget to upload this file?

[flackr, 2016/10/11 12:49:01]

I certainly did, it's added now.

+  navigateTo(m_baseURL + "sticky-position.html");
+  forceFullCompositingUpdate();
+
+  // Sticky position should not fall back to main thread scrolling.
+  WebLayer* rootScrollLayer = getRootScrollLayer();
+  EXPECT_FALSE(rootScrollLayer->shouldScrollOnMainThread());
+
+  Document* document = frame()->document();
+  {
+    Element* element = document->getElementById("div-tl");
+    ASSERT_TRUE(element);
+    WebLayer* layer = webLayerFromElement(element);
+    ASSERT_TRUE(layer);
+    WebLayerStickyPositionConstraint constraint =
+        layer->stickyPositionConstraint();
+    ASSERT_TRUE(constraint.isSticky);
+    EXPECT_TRUE(constraint.isAnchoredTop && constraint.isAnchoredLeft &&
+                !constraint.isAnchoredRight && !constraint.isAnchoredBottom);
+    EXPECT_EQ(1.f, constraint.topOffset);
+    EXPECT_EQ(1.f, constraint.leftOffset);
+    EXPECT_EQ(IntRect(100, 100, 10, 10),
+              IntRect(constraint.scrollContainerRelativeStickyBoxRect));
+    EXPECT_EQ(IntRect(100, 100, 200, 200),
+              IntRect(constraint.scrollContainerRelativeContainingBlockRect));
+    EXPECT_EQ(IntPoint(100, 100),
+              IntPoint(constraint.parentRelativeStickyBoxOffset));
+  }
+  {
+    Element* element = document->getElementById("div-tr");
+    ASSERT_TRUE(element);
+    WebLayer* layer = webLayerFromElement(element);
+    ASSERT_TRUE(layer);
+    WebLayerStickyPositionConstraint constraint =
+        layer->stickyPositionConstraint();
+    ASSERT_TRUE(constraint.isSticky);
+    EXPECT_TRUE(constraint.isAnchoredTop && !constraint.isAnchoredLeft &&
+                constraint.isAnchoredRight && !constraint.isAnchoredBottom);
+  }
+  {
+    Element* element = document->getElementById("div-bl");
+    ASSERT_TRUE(element);
+    WebLayer* layer = webLayerFromElement(element);
+    ASSERT_TRUE(layer);
+    WebLayerStickyPositionConstraint constraint =
+        layer->stickyPositionConstraint();
+    ASSERT_TRUE(constraint.isSticky);
+    EXPECT_TRUE(!constraint.isAnchoredTop && constraint.isAnchoredLeft &&
+                !constraint.isAnchoredRight && constraint.isAnchoredBottom);
+  }
+  {
+    Element* element = document->getElementById("div-br");
+    ASSERT_TRUE(element);
+    WebLayer* layer = webLayerFromElement(element);
+    ASSERT_TRUE(layer);
+    WebLayerStickyPositionConstraint constraint =
+        layer->stickyPositionConstraint();
+    ASSERT_TRUE(constraint.isSticky);
+    EXPECT_TRUE(!constraint.isAnchoredTop && !constraint.isAnchoredLeft &&
+                constraint.isAnchoredRight && constraint.isAnchoredBottom);
+  }
+  {
+    Element* element = document->getElementById("span-tl");
+    ASSERT_TRUE(element);
+    WebLayer* layer = webLayerFromElement(element);
+    ASSERT_TRUE(layer);
+    WebLayerStickyPositionConstraint constraint =
+        layer->stickyPositionConstraint();
+    ASSERT_TRUE(constraint.isSticky);
+    EXPECT_TRUE(constraint.isAnchoredTop && constraint.isAnchoredLeft &&
+                !constraint.isAnchoredRight && !constraint.isAnchoredBottom);
+  }
+  {
+    Element* element = document->getElementById("span-tlbr");
+    ASSERT_TRUE(element);
+    WebLayer* layer = webLayerFromElement(element);
+    ASSERT_TRUE(layer);
+    WebLayerStickyPositionConstraint constraint =
+        layer->stickyPositionConstraint();
+    ASSERT_TRUE(constraint.isSticky);
+    EXPECT_TRUE(constraint.isAnchoredTop && constraint.isAnchoredLeft &&
+                constraint.isAnchoredRight && constraint.isAnchoredBottom);
+    EXPECT_EQ(1.f, constraint.topOffset);
+    EXPECT_EQ(1.f, constraint.leftOffset);
+    EXPECT_EQ(1.f, constraint.rightOffset);
+    EXPECT_EQ(1.f, constraint.bottomOffset);
+  }
+  {
+    Element* element = document->getElementById("composited-top");
+    ASSERT_TRUE(element);
+    WebLayer* layer = webLayerFromElement(element);
+    ASSERT_TRUE(layer);
+    WebLayerStickyPositionConstraint constraint =
+        layer->stickyPositionConstraint();
+    ASSERT_TRUE(constraint.isSticky);
+    EXPECT_TRUE(constraint.isAnchoredTop);
+    EXPECT_EQ(IntRect(100, 110, 10, 10),
+              IntRect(constraint.scrollContainerRelativeStickyBoxRect));
+    EXPECT_EQ(IntRect(100, 100, 200, 200),
+              IntRect(constraint.scrollContainerRelativeContainingBlockRect));
+    EXPECT_EQ(IntPoint(0, 10),
+              IntPoint(constraint.parentRelativeStickyBoxOffset));
+  }
+}
+
 TEST_F(ScrollingCoordinatorTest, touchEventHandler) {
   registerMockedHttpURLLoad("touch-event-handler.html");
   navigateTo(m_baseURL + "touch-event-handler.html");
   forceFullCompositingUpdate();
 
   ASSERT_EQ(WebEventListenerProperties::Blocking,
             webLayerTreeView()->eventListenerProperties(
                 WebEventListenerClass::TouchStartOrMove));
 }
 
@@ skipping 394 matching lines @@
   forceFullCompositingUpdate();
   scrollbarGraphicsLayer = compositedLayerMapping->layerForVerticalScrollbar();
   ASSERT_FALSE(
       scrollbarGraphicsLayer->platformLayer()->shouldScrollOnMainThread());
   ASSERT_FALSE(
       scrollbarGraphicsLayer->platformLayer()->mainThreadScrollingReasons() &
       MainThreadScrollingReason::kCustomScrollbarScrolling);
 }
 
 }  // namespace blink