Improve handling of PaintInvalidationLayer (renamed to PaintInvalidationSubtree)

third_party/WebKit/Source/core/layout/PaintInvalidationState.h

Index: third_party/WebKit/Source/core/layout/PaintInvalidationState.h
diff --git a/third_party/WebKit/Source/core/layout/PaintInvalidationState.h b/third_party/WebKit/Source/core/layout/PaintInvalidationState.h
index 196cbf9b3d6af364571960c31cd6a1890073446b..a57194e1313ba012e3de59969f0c5c2c8929f11c 100644
--- a/third_party/WebKit/Source/core/layout/PaintInvalidationState.h
+++ b/third_party/WebKit/Source/core/layout/PaintInvalidationState.h
@@ -7,6 +7,7 @@
 
 #include "core/CoreExport.h"
 #include "platform/geometry/LayoutRect.h"
+#include "platform/graphics/PaintInvalidationReason.h"
 #include "platform/transforms/AffineTransform.h"
 #include "wtf/Allocator.h"
 #include "wtf/Noncopyable.h"
@@ -51,13 +52,17 @@ public:
     // local space (border box space for LayoutBoxes). After invalidation of the current object,
     // before invalidation of the subtrees, this method must be called to apply clip and scroll offset
     // etc. for creating child PaintInvalidationStates.
-    void updateForChildren();
+    void updateForChildren(PaintInvalidationReason);
 
-    bool forcedSubtreeInvalidationWithinContainer() const { return m_forcedSubtreeInvalidationWithinContainer; }
-    void setForceSubtreeInvalidationWithinContainer() { m_forcedSubtreeInvalidationWithinContainer = true; }
+    bool hasForcedSubtreeInvalidationFlags() const { return m_forcedSubtreeInvalidationFlags; }
 
-    bool forcedSubtreeInvalidationRectUpdateWithinContainer() const { return m_forcedSubtreeInvalidationRectUpdateWithinContainer; }
-    void setForceSubtreeInvalidationRectUpdateWithinContainer() { m_forcedSubtreeInvalidationRectUpdateWithinContainer = true; }
+    bool forcedSubtreeInvalidationCheckingWithinContainer() const { return m_forcedSubtreeInvalidationFlags & InvalidationChecking; }
+    void setForceSubtreeInvalidationCheckingWithinContainer() { m_forcedSubtreeInvalidationFlags |= InvalidationChecking; }
+
+    bool forcedSubtreeFullInvalidationWithinContainer() const { return m_forcedSubtreeInvalidationFlags & FullInvalidation; }
+
+    bool forcedSubtreeInvalidationRectUpdateWithinContainerOnly() const { return m_forcedSubtreeInvalidationFlags == InvalidationRectUpdate; }
+    void setForceSubtreeInvalidationRectUpdateWithinContainer() { m_forcedSubtreeInvalidationFlags |= InvalidationRectUpdate; }
 
     const LayoutBoxModelObject& paintInvalidationContainer() const { return *m_paintInvalidationContainer; }
 
@@ -95,8 +100,13 @@ private:
 
     const LayoutObject& m_currentObject;
 
-    bool m_forcedSubtreeInvalidationWithinContainer;
-    bool m_forcedSubtreeInvalidationRectUpdateWithinContainer;
+    enum ForcedSubtreeInvalidationFlag {
+        InvalidationChecking = 1 << 0,
+        InvalidationRectUpdate = 1 << 1,
+        FullInvalidation = 1 << 2,
+        FullInvalidationForStackedContents = 1 << 3,
+    };
+    unsigned m_forcedSubtreeInvalidationFlags;
 
     bool m_clipped;
     bool m_clippedForAbsolutePosition;