cc: Enable composited border-radius scrolling.

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 1116 matching lines @@
   TestNonCompositedReasons("transform",
                            MainThreadScrollingReason::kHasTransformAndLCDText);
 }
 
 TEST_P(NonCompositedMainThreadScrollingReasonTest, BackgroundNotOpaqueTest) {
   TestNonCompositedReasons(
       "background-not-opaque",
       MainThreadScrollingReason::kBackgroundNotOpaqueInRectAndLCDText);
 }
 
-TEST_P(NonCompositedMainThreadScrollingReasonTest, BorderRadiusTest) {
-  TestNonCompositedReasons("border-radius",
-                           MainThreadScrollingReason::kHasBorderRadius);
-}
-
 TEST_P(NonCompositedMainThreadScrollingReasonTest, ClipTest) {
   TestNonCompositedReasons("clip",
                            MainThreadScrollingReason::kHasClipRelatedProperty);
 }
 
 TEST_P(NonCompositedMainThreadScrollingReasonTest, ClipPathTest) {
   uint32_t clip_reason = MainThreadScrollingReason::kHasClipRelatedProperty;
   GetWebView()->GetSettings()->SetPreferCompositingToLCDTextEnabled(false);
   Document* document = GetFrame()->GetDocument();
   // Test ancestor with ClipPath
@@ skipping 35 matching lines @@
 
   // Remove clip path from descendant.
   element->removeAttribute(HTMLNames::styleAttr);
   ForceFullCompositingUpdate();
   EXPECT_FALSE(scrollable_area->GetNonCompositedMainThreadScrollingReasons() &
                clip_reason);
   EXPECT_FALSE(frame_view->GetMainThreadScrollingReasons() & clip_reason);
 }
 
 TEST_P(NonCompositedMainThreadScrollingReasonTest, LCDTextEnabledTest) {
-  TestNonCompositedReasons("transparent border-radius",
-                           MainThreadScrollingReason::kHasOpacityAndLCDText |
-                               MainThreadScrollingReason::kHasBorderRadius);
+  TestNonCompositedReasons("transparent",
+                           MainThreadScrollingReason::kHasOpacityAndLCDText);
 }
 
 TEST_P(NonCompositedMainThreadScrollingReasonTest, BoxShadowTest) {
   TestNonCompositedReasons(
       "box-shadow", MainThreadScrollingReason::kHasBoxShadowFromNonRootLayer);
 }
 
 TEST_P(NonCompositedMainThreadScrollingReasonTest, StackingContextTest) {
   GetWebView()->GetSettings()->SetPreferCompositingToLCDTextEnabled(false);
 
@@ skipping 34 matching lines @@
   Element* container = document->getElementById("scroller1");
   ASSERT_TRUE(container);
   container->setAttribute("class", "composited transparent",
                           ASSERT_NO_EXCEPTION);
   ForceFullCompositingUpdate();
 
   PaintLayerScrollableArea* scrollable_area =
       ToLayoutBoxModelObject(container->GetLayoutObject())->GetScrollableArea();
   ASSERT_TRUE(scrollable_area);
   EXPECT_FALSE(scrollable_area->GetNonCompositedMainThreadScrollingReasons());
-
-  Element* container2 = document->getElementById("scroller2");

[chrishtr, 2017/06/16 22:34:34]

Please add a unittest here that it *does* composited scroll with border-radius.

[sunxd, 2017/06/20 14:36:10]

Done.

-  ASSERT_TRUE(container2);
-  container2->setAttribute("class", "composited border-radius",
-                           ASSERT_NO_EXCEPTION);
-  ForceFullCompositingUpdate();
-  PaintLayerScrollableArea* scrollable_area2 =
-      ToLayoutBoxModelObject(container2->GetLayoutObject())
-          ->GetScrollableArea();
-  ASSERT_TRUE(scrollable_area2);
-  EXPECT_TRUE(scrollable_area2->GetNonCompositedMainThreadScrollingReasons() &
-              MainThreadScrollingReason::kHasBorderRadius);
 }
 
 }  // namespace blink