Paint local attachment backgrounds into composited scrolling contents layer

third_party/WebKit/Source/core/layout/LayoutBoxTest.cpp

Index: third_party/WebKit/Source/core/layout/LayoutBoxTest.cpp
diff --git a/third_party/WebKit/Source/core/layout/LayoutBoxTest.cpp b/third_party/WebKit/Source/core/layout/LayoutBoxTest.cpp
index e89af5b107787ae323f747ebc74f500f58fcfcd8..5d7f480a49cbad84194fba7e821b15cf1653ae13 100644
--- a/third_party/WebKit/Source/core/layout/LayoutBoxTest.cpp
+++ b/third_party/WebKit/Source/core/layout/LayoutBoxTest.cpp
@@ -24,4 +24,13 @@ TEST_F(LayoutBoxTest, BackgroundObscuredInRect)
     ASSERT_TRUE(layoutObject->backgroundIsKnownToBeObscured());
 }
 
+TEST_F(LayoutBoxTest, BackgroundRect)

[chrishtr, 2016/08/12 17:03:00]

Add more tests for other cases.

[flackr, 2016/08/16 17:52:51]

I added tests which I think cover all of the special cases - let me know if you
think I missed any.

+{
+    setBodyInnerHTML("<style>#target { background: url(data:image/png;base64,iVBORw0KGgoAAAANSUhEUg) border-box, green content-box; width: 100px; height: 100px; padding: 10px; border: 10px solid black;}</style>"
+        "<div id='target'></div>");
+    LayoutBox* layoutBox = toLayoutBox(getLayoutObjectByElementId("target"));
+    EXPECT_EQ(LayoutRect(20, 20, 100, 100), layoutBox->backgroundRect(OpaqueBackgroundRect));
+    EXPECT_EQ(LayoutRect(0, 0, 140, 140), layoutBox->backgroundRect(TranslucentBackgroundRect));
+}
+
 } // namespace blink