Remove remaining traces of CreateGpuMemoryBufferImageCHROMIUM

ppapi/proxy/ppapi_command_buffer_proxy.h

Index: ppapi/proxy/ppapi_command_buffer_proxy.h
diff --git a/ppapi/proxy/ppapi_command_buffer_proxy.h b/ppapi/proxy/ppapi_command_buffer_proxy.h
index 24427f60bc1e48839f25a231917e650c19ea464c..5f43ed4d88e512cce5cabe329ba858bf5ce8b50a 100644
--- a/ppapi/proxy/ppapi_command_buffer_proxy.h
+++ b/ppapi/proxy/ppapi_command_buffer_proxy.h
@@ -59,10 +59,6 @@ class PPAPI_PROXY_EXPORT PpapiCommandBufferProxy : public gpu::CommandBuffer,
                       size_t height,
                       unsigned internalformat) override;
   void DestroyImage(int32_t id) override;
-  int32_t CreateGpuMemoryBufferImage(size_t width,
-                                     size_t height,
-                                     unsigned internalformat,
-                                     unsigned usage) override;
   void SignalQuery(uint32_t query, const base::Closure& callback) override;
   void SetLock(base::Lock*) override;
   void EnsureWorkVisible() override;