[repaint-after-layout] Skip invalidations if our RenderView did a full invalidation.

Source/core/frame/FrameView.cpp

Index: Source/core/frame/FrameView.cpp
diff --git a/Source/core/frame/FrameView.cpp b/Source/core/frame/FrameView.cpp
index 3a1ec6409f82112ae332983736e9b0e71a77c387..b9df752249123de673a975e6be51d62d84905605 100644
--- a/Source/core/frame/FrameView.cpp
+++ b/Source/core/frame/FrameView.cpp
@@ -1037,7 +1037,17 @@ void FrameView::repaintTree(RenderObject* root)
     // Until those states are fully fledged, I'll just disable the ASSERTS.
     DisableCompositingQueryAsserts disabler;
 
+    bool renderViewDidFullInvalidation = false;
+
     for (RenderObject* renderer = root; renderer; renderer = renderer->nextInPreOrder()) {
+        // If the RenderView did a full invalidation, and that's the view that we're part
+        // of, skip issuing invalidations for the RenderObject as it will be
+        // covered by the RenderView invalidation.
+        if (!renderer->hasLayer() && renderer != root && (renderer->view() == root) && renderViewDidFullInvalidation) {

[Julien - ping for review, 2014/03/27 22:37:26]

I don't think we should check hasLayer() here as it's conceptually wrong to
treat renderers with a layer differently (especially in the world where
repaint-after-layout has super-seeded RenderLayerRepainter).

[dsinclair, 2014/03/28 18:35:26]

Done.

+            renderer->clearRepaintState();
+            continue;
+        }
+
         const LayoutRect& oldRepaintRect = renderer->oldRepaintRect();
         const LayoutRect& newRepaintRect = renderer->newRepaintRect();
 
@@ -1048,6 +1058,9 @@ void FrameView::repaintTree(RenderObject* root)
             renderer->setShouldDoFullRepaintAfterLayout(true);
         }
 
+        if (renderer == root && root->isRenderView())

[Julien - ping for review, 2014/03/27 22:37:26]

Note that this check will be run for each renderer when it's only needed for the
view. This obscures the intent pretty badly. I would rather have that checked
above with a fast path.

[dsinclair, 2014/03/28 18:35:26]

Done.

+            renderViewDidFullInvalidation = renderer->shouldDoFullRepaintAfterLayout();
+
         // FIXME: Currently renderers with layers will get repainted when we call updateLayerPositionsAfterLayout.
         // That call should be broken apart to position the layers be done before
         // the repaintTree call so this will repaint everything.