Simplify the paint invalidation bits.

sky/engine/core/rendering/style/RenderStyle.h

Index: sky/engine/core/rendering/style/RenderStyle.h
diff --git a/sky/engine/core/rendering/style/RenderStyle.h b/sky/engine/core/rendering/style/RenderStyle.h
index 42c3985315b00bd62be1b889adaabc3ba7f6dd28..95d0550774aae5114158f05efc11413c696d7328 100644
--- a/sky/engine/core/rendering/style/RenderStyle.h
+++ b/sky/engine/core/rendering/style/RenderStyle.h
@@ -1366,10 +1366,10 @@ private:
 
     void addAppliedTextDecoration(const AppliedTextDecoration&);
 
+    // FIXME(sky): Combine these first two.
     bool diffNeedsFullLayoutAndPaintInvalidation(const RenderStyle& other) const;
     bool diffNeedsFullLayout(const RenderStyle& other) const;
-    bool diffNeedsPaintInvalidationLayer(const RenderStyle& other) const;
-    bool diffNeedsPaintInvalidationObject(const RenderStyle& other) const;
+    bool diffNeedsPaintInvalidation(const RenderStyle& other) const;
     bool diffNeedsRecompositeLayer(const RenderStyle& other) const;
     void updatePropertySpecificDifferences(const RenderStyle& other, StyleDifference&) const;
 };