cc: Never block on uploads from previous frame and increase max pending uploads.

cc/CCLayerTreeHostImpl.cpp

Index: cc/CCLayerTreeHostImpl.cpp
diff --git a/cc/CCLayerTreeHostImpl.cpp b/cc/CCLayerTreeHostImpl.cpp
index 00a23a7057710a7e565ddcdf7a6d69f9f3a0e67d..c9255a52cdbd572af2f33affa105898496af8559 100644
--- a/cc/CCLayerTreeHostImpl.cpp
+++ b/cc/CCLayerTreeHostImpl.cpp
@@ -29,6 +29,7 @@
 #include "CCScrollbarLayerImpl.h"
 #include "CCSettings.h"
 #include "CCSingleThreadProxy.h"
+#include "TextureUploader.h"
 #include "TraceEvent.h"
 #include <wtf/CurrentTime.h>
 #include <algorithm>
@@ -585,6 +586,10 @@ void CCLayerTreeHostImpl::didDrawAllLayers(const FrameData& frame)
 {
     for (size_t i = 0; i < frame.willDrawLayers.size(); ++i)
         frame.willDrawLayers[i]->didDraw(m_resourceProvider.get());
+
+    // Once all layers have been drawn, pending texture uploads should no
+    // longer block future uploads.
+    m_resourceProvider->textureUploader()->markPendingUploadsAsNonBlocking();
 }
 
 void CCLayerTreeHostImpl::finishAllRendering()