Alternate way to track first paint

Source/core/rendering/RenderObject.h

Index: Source/core/rendering/RenderObject.h
diff --git a/Source/core/rendering/RenderObject.h b/Source/core/rendering/RenderObject.h
index 4240104a777bbc1705e35be228d42a2f9e693870..68cd625b89dd77323b413a794bb1b07fce5f58a2 100644
--- a/Source/core/rendering/RenderObject.h
+++ b/Source/core/rendering/RenderObject.h
@@ -115,6 +115,7 @@ enum InvalidationReason {
     InvalidationScroll,
     InvalidationSelection,
     InvalidationLayer,
+    InvalidationRendererInsertion,
     InvalidationRendererRemoval,
     InvalidationPaintRectangle
 };
@@ -831,9 +832,6 @@ public:
 
     void getTextDecorations(unsigned decorations, AppliedTextDecoration& underline, AppliedTextDecoration& overline, AppliedTextDecoration& linethrough, bool quirksMode = false, bool firstlineStyle = false);
 
-    void setHadPaintInvalidation();
-    bool hadPaintInvalidation() const;
-
     // Return the RenderLayerModelObject in the container chain which is responsible for painting this object, or 0
     // if painting is root-relative. This is the container that should be passed to the 'forPaintInvalidation'
     // methods.
@@ -1015,8 +1013,9 @@ public:
     const LayoutPoint& previousPositionFromPaintInvalidationBacking() const { return m_previousPositionFromPaintInvalidationBacking; }
     void setPreviousPositionFromPaintInvalidationBacking(const LayoutPoint& positionFromPaintInvalidationBacking) { m_previousPositionFromPaintInvalidationBacking = positionFromPaintInvalidationBacking; }
 
-    bool shouldDoFullPaintInvalidation() const { return m_bitfields.shouldDoFullPaintInvalidation(); }
+    bool shouldDoFullPaintInvalidation() const { return m_bitfields.fullPaintInvalidationReason() != InvalidationNone; }
     void setShouldDoFullPaintInvalidation(bool, MarkingBehavior = MarkContainingBlockChain);
+    void setShouldDoFullPaintInvalidationWithReason(InvalidationReason = InvalidationFull, MarkingBehavior = MarkContainingBlockChain);

[Julien - ping for review, 2014/09/26 17:56:24]

I am not a huge fan of this API:
- We can call setShouldDoFullPaintInvalidationWithReason(InvalidationReasonNone)
:(
- Overusing default parameters make the code less readable (here people may not
see what happens if you call it without parameter).

[Xianzhu, 2014/09/26 18:36:21]

Acknowledged.

 
     bool shouldInvalidateOverflowForPaint() const { return m_bitfields.shouldInvalidateOverflowForPaint(); }
 
@@ -1198,7 +1197,6 @@ private:
     public:
         RenderObjectBitfields(Node* node)
             : m_selfNeedsLayout(false)
-            , m_shouldDoFullPaintInvalidation(false)
             , m_shouldInvalidateOverflowForPaint(false)
             , m_shouldDoFullPaintInvalidationIfSelfPaintingLayer(false)
             // FIXME: We should remove mayNeedPaintInvalidation once we are able to
@@ -1237,12 +1235,12 @@ private:
             , m_selectionState(SelectionNone)
             , m_flowThreadState(NotInsideFlowThread)
             , m_boxDecorationBackgroundState(NoBoxDecorationBackground)
+            , m_fullPaintInvalidationReason(InvalidationNone)
         {
         }
 
         // 32 bits have been used in the first word, and 11 in the second.
         ADD_BOOLEAN_BITFIELD(selfNeedsLayout, SelfNeedsLayout);
-        ADD_BOOLEAN_BITFIELD(shouldDoFullPaintInvalidation, ShouldDoFullPaintInvalidation);
         ADD_BOOLEAN_BITFIELD(shouldInvalidateOverflowForPaint, ShouldInvalidateOverflowForPaint);
         ADD_BOOLEAN_BITFIELD(shouldDoFullPaintInvalidationIfSelfPaintingLayer, ShouldDoFullPaintInvalidationIfSelfPaintingLayer);
         ADD_BOOLEAN_BITFIELD(mayNeedPaintInvalidation, MayNeedPaintInvalidation);
@@ -1290,6 +1288,7 @@ private:
         unsigned m_selectionState : 3; // SelectionState
         unsigned m_flowThreadState : 2; // FlowThreadState
         unsigned m_boxDecorationBackgroundState : 2; // BoxDecorationBackgroundState
+        unsigned m_fullPaintInvalidationReason : 4; // InvalidationReason
 
     public:
         bool isOutOfFlowPositioned() const { return m_positionedState == IsOutOfFlowPositioned; }
@@ -1311,6 +1310,13 @@ private:
 
         ALWAYS_INLINE BoxDecorationBackgroundState boxDecorationBackgroundState() const { return static_cast<BoxDecorationBackgroundState>(m_boxDecorationBackgroundState); }
         ALWAYS_INLINE void setBoxDecorationBackgroundState(BoxDecorationBackgroundState s) { m_boxDecorationBackgroundState = s; }
+
+        InvalidationReason fullPaintInvalidationReason() const { return static_cast<InvalidationReason>(m_fullPaintInvalidationReason); }
+        void setFullPaintInvalidationReason(InvalidationReason reason)
+        {
+            ASSERT(reason != InvalidationIncremental);
+            m_fullPaintInvalidationReason = reason;
+        }
     };
 
 #undef ADD_BOOLEAN_BITFIELD