[RAL] Make sure RenderLayers are invalidated when moved.

Source/core/rendering/RenderBlock.cpp

Index: Source/core/rendering/RenderBlock.cpp
diff --git a/Source/core/rendering/RenderBlock.cpp b/Source/core/rendering/RenderBlock.cpp
index a95ad9ee2a5fb8d4cc81f71a43687feab0881aa4..0f7aa6254f44206346c55c06f55b142b38ca35cd 100644
--- a/Source/core/rendering/RenderBlock.cpp
+++ b/Source/core/rendering/RenderBlock.cpp
@@ -365,18 +365,20 @@ void RenderBlock::styleDidChange(StyleDifference diff, const RenderStyle* oldSty
 
 void RenderBlock::repaintTreeAfterLayout(const RenderLayerModelObject& repaintContainer)
 {
-    if (!shouldCheckForInvalidationAfterLayout())
-        return;
+    // Note, we don't want to early out here using shouldCheckForInvalidationAfterLayout as
+    // we have to make sure we go through any positioned objects as they won't be seen in
+    // the normal tree walk.
 
-    RenderBox::repaintTreeAfterLayout(repaintContainer);
+    if (shouldCheckForInvalidationAfterLayout())
+        RenderBox::repaintTreeAfterLayout(repaintContainer);
 
     // Take care of positioned objects. This is required as LayoutState keeps a single clip rect.
     if (TrackedRendererListHashSet* positionedObjects = this->positionedObjects()) {
         TrackedRendererListHashSet::iterator end = positionedObjects->end();
         LayoutStateMaintainer statePusher(*this, isTableRow() ? LayoutSize() : locationOffset());
+
         for (TrackedRendererListHashSet::iterator it = positionedObjects->begin(); it != end; ++it) {
             RenderBox* box = *it;
-
             // One of the renderers we're skipping over here may be the child's repaint container,
             // so we can't pass our own repaint container along.
             const RenderLayerModelObject& repaintContainerForChild = *box->containerForRepaint();