cc: Add GpuMemoryBufferId to TextureMailbox

third_party/WebKit/public/platform/WebExternalTextureMailbox.h

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 22 matching lines @@
 
 #include "WebSize.h"
 
 namespace blink {
 
 struct WebExternalTextureMailbox {
     signed char name[64];
     signed char syncToken[24];
     bool validSyncToken = false;
     bool allowOverlay = false;
     bool nearestNeighbor = false;

[ccameron, 2016/05/11 22:18:14]

This will need to be populated for the GMB-backed resources created in Blink
(canvas, webgl, etc).

+    unsigned gpuMemoryBufferId = 0;
     unsigned textureTarget = 0;
     WebSize textureSize;
 
     WebExternalTextureMailbox()
     {
         memset(name, 0, sizeof(name));
         memset(syncToken, 0, sizeof(syncToken));
     }
 };
 
 inline bool nameEquals(const WebExternalTextureMailbox& a, const WebExternalTextureMailbox& b)
 {
     return !memcmp(a.name, b.name, sizeof(a.name));
 }
 
 } // namespace blink
 
 #endif // WebExternalTextureMailbox_h