cc: Add asynchronous setPixel interface.

cc/resource_provider.h

Index: cc/resource_provider.h
diff --git a/cc/resource_provider.h b/cc/resource_provider.h
index 3d7b208b01bd69f8367fce2be4041356d9e67512..6dad7e96025a942b5599b49ed4aab15c0c7f8e8b 100644
--- a/cc/resource_provider.h
+++ b/cc/resource_provider.h
@@ -209,6 +209,11 @@ public:
     // Update pixels from acquired pixel buffer.
     void setPixelsFromBuffer(ResourceId id);
 
+    // Asynchronously update pixels from acquired pixel buffer.
+    void beginSetPixels(ResourceId id);

[piman, 2012/11/27 00:40:01]

naming nit: I would name this something like setPixelsFromBufferAsync. The
reason is that it does the same thing as setPixelsFromBuffer, but
asynchronously.

'begin' makes me look for an 'end'

+    bool didSetPixelsComplete(ResourceId id);
+    void abortSetPixels(ResourceId id);
+
 private:
     struct Resource {
         Resource();
@@ -218,6 +223,8 @@ private:
         unsigned glId;
         // Pixel buffer used for set pixels without unnecessary copying.
         unsigned glPixelBufferId;
+        // Query used to determine when asynchronous set pixels complete.
+        unsigned glUploadQueryId;
         Mailbox mailbox;
         uint8_t* pixels;
         uint8_t* pixelBuffer;