Merge 125799 - [chromium] Impl scrolling crashes when the renderer's initialization failed

Source/WebCore/platform/graphics/chromium/cc/CCLayerTreeHostImpl.cpp

Index: Source/WebCore/platform/graphics/chromium/cc/CCLayerTreeHostImpl.cpp
===================================================================
--- Source/WebCore/platform/graphics/chromium/cc/CCLayerTreeHostImpl.cpp	(revision 125940)
+++ Source/WebCore/platform/graphics/chromium/cc/CCLayerTreeHostImpl.cpp	(working copy)
@@ -251,6 +251,7 @@
 {
     ASSERT(renderSurfaceLayerList.isEmpty());
     ASSERT(m_rootLayerImpl);
+    ASSERT(m_layerRenderer); // For maxTextureSize.
 
     {
         TRACE_EVENT0("cc", "CCLayerTreeHostImpl::calcDrawEtc");
@@ -824,6 +825,8 @@
 {
     if (!m_rootLayerImpl)
         return false;
+    if (!m_layerRenderer)
+        return false;
 
     // We need both a non-empty render surface layer list and a root render
     // surface to be able to iterate over the visible layers.