Fix issues of display item client cache flags

third_party/WebKit/Source/core/paint/PaintControllerPaintTest.cpp

Index: third_party/WebKit/Source/core/paint/PaintControllerPaintTest.cpp
diff --git a/third_party/WebKit/Source/core/paint/PaintControllerPaintTest.cpp b/third_party/WebKit/Source/core/paint/PaintControllerPaintTest.cpp
index 6f0e06e53564bcb6c90491d8103468fb997f45af..f226e8b872efdbde37720e8587a40518e86366a1 100644
--- a/third_party/WebKit/Source/core/paint/PaintControllerPaintTest.cpp
+++ b/third_party/WebKit/Source/core/paint/PaintControllerPaintTest.cpp
@@ -8,6 +8,7 @@
 #include "core/layout/line/InlineTextBox.h"
 #include "core/page/FocusController.h"
 #include "core/paint/LayoutObjectDrawingRecorder.h"
+#include "core/paint/ObjectPaintProperties.h"
 #include "core/paint/PaintLayerPainter.h"
 #include "platform/graphics/GraphicsContext.h"
 #include "platform/graphics/paint/DrawingDisplayItem.h"
@@ -63,4 +64,33 @@ TEST_P(PaintControllerPaintTestForSlimmingPaintV1AndV2, InlineRelayout)
         TestDisplayItem(secondTextBox, foregroundType));
 }
 
+TEST_F(PaintControllerPaintTestForSlimmingPaintV2, ChunkIdClientCacheFlag)
+{
+    setBodyInnerHTML(
+        "<div id='div' style='width: 200px; height: 200px; opacity: 0.5'>"

[chrishtr, 2016/07/27 19:18:34]

Why does this use case cause cache skipping?

[Xianzhu, 2016/07/27 19:25:55]

This doesn't test cache skipping, but test the isJustCreated flag of chunk
client.

I don't have idea about testing cache skipping yet, but your compositing change
will cover it.

[chrishtr, 2016/07/27 19:28:25]

Why is line 92 indicating that the client cache is not valid then?

As for testing: cache skipping is unittested in PaintControllerTest. I think you
can add an assert that the DisplayItemClient was marked as
uncached, where previously it was not.

[Xianzhu, 2016/07/27 19:43:38]

Added comment. A client is validly cached only if it has validly cached display
items (now and no display items skipped cache).
Added PaintControllerTest.PartialSkipCache.

+        "  <div style='width: 100px; height: 100px; background-color: blue'></div>"
+        "</div>");
+    PaintLayer& htmlLayer = *toLayoutBoxModelObject(document().documentElement()->layoutObject())->layer();
+    LayoutBlock& div = *toLayoutBlock(getLayoutObjectByElementId("div"));
+    LayoutObject& subDiv = *div.firstChild();
+
+    EXPECT_DISPLAY_LIST(rootPaintController().getDisplayItemList(), 6,
+        TestDisplayItem(layoutView(), documentBackgroundType),
+        TestDisplayItem(htmlLayer, DisplayItem::Subsequence),
+        TestDisplayItem(div, DisplayItem::BeginCompositing),
+        TestDisplayItem(subDiv, backgroundType),
+        TestDisplayItem(div, DisplayItem::EndCompositing),
+        TestDisplayItem(htmlLayer, DisplayItem::EndSubsequence));
+
+    const EffectPaintPropertyNode* effectNode = div.objectPaintProperties()->effect();
+    EXPECT_EQ(0.5f, effectNode->opacity());
+    const PaintChunk& chunk = rootPaintController().paintChunks()[1];
+    EXPECT_EQ(*div.layer(), chunk.id->client);
+    EXPECT_EQ(effectNode, chunk.properties.effect.get());
+
+    EXPECT_FALSE(div.layer()->isJustCreated());
+    EXPECT_FALSE(rootPaintController().clientCacheIsValid(div));
+    EXPECT_TRUE(rootPaintController().clientCacheIsValid(subDiv));
+}
+
 } // namespace blink