WebKit merge 40668:40722 part 1.

third_party/WebKit/WebCore/rendering/RenderWidget.cpp

Index: third_party/WebKit/WebCore/rendering/RenderWidget.cpp
===================================================================
--- third_party/WebKit/WebCore/rendering/RenderWidget.cpp	(revision 9310)
+++ third_party/WebKit/WebCore/rendering/RenderWidget.cpp	(working copy)
@@ -91,20 +91,20 @@
     if (hasOverrideSize())
         setOverrideSize(-1);
 
-    RenderLayer* layer = m_layer;
     RenderArena* arena = renderArena();
 
-    if (layer)
-        layer->clearClipRects();
+    if (hasLayer())
+        layer()->clearClipRects();
 
     if (style() && (style()->height().isPercent() || style()->minHeight().isPercent() || style()->maxHeight().isPercent()))
         RenderBlock::removePercentHeightDescendant(this);
 
     setNode(0);
+
+    if (hasLayer())
+        layer()->destroy(arena);
+
     deref(arena);
-
-    if (layer)
-        layer->destroy(arena);
 }
 
 RenderWidget::~RenderWidget()