Add GL_CHROMIUM_texture_mailbox entrypoints to wgc3d implementations

webkit/gpu/webgraphicscontext3d_in_process_impl.h

Index: webkit/gpu/webgraphicscontext3d_in_process_impl.h
diff --git a/webkit/gpu/webgraphicscontext3d_in_process_impl.h b/webkit/gpu/webgraphicscontext3d_in_process_impl.h
index 293dd05699f508127b3e97a0b518f612278dd498..0b248ce0c62c264a5bf49bafb199a091f3b74dfa 100644
--- a/webkit/gpu/webgraphicscontext3d_in_process_impl.h
+++ b/webkit/gpu/webgraphicscontext3d_in_process_impl.h
@@ -24,6 +24,7 @@ class GLSurface;
 class GLShareGroup;
 }
 
+using WebKit::WGC3Dbyte;
 using WebKit::WGC3Dchar;
 using WebKit::WGC3Denum;
 using WebKit::WGC3Dboolean;
@@ -482,6 +483,12 @@ class WebGraphicsContext3DInProcessImpl : public WebGraphicsContext3D {
   // Only applies to contexts that use the command buffer.
   virtual void shallowFlushCHROMIUM() { }
 
+  virtual void genMailboxCHROMIUM(WGC3Dbyte* mailbox);
+  virtual void produceTextureCHROMIUM(WGC3Denum target,
+                                      const WGC3Dbyte* mailbox);
+  virtual void consumeTextureCHROMIUM(WGC3Denum target,
+                                      const WGC3Dbyte* mailbox);
+
  protected:
   virtual GrGLInterface* onCreateGrGLInterface();