Expose GpuMemoryBufferId through glGetImageivCHROMIUM.

gpu/gles2_conform_support/egl/context.cc

Index: gpu/gles2_conform_support/egl/context.cc
diff --git a/gpu/gles2_conform_support/egl/context.cc b/gpu/gles2_conform_support/egl/context.cc
index 07dc5ae28e4c51dd93df4990d482180db7d57e63..63d851c0d43fce709623edb18d0bdc20590c8a66 100644
--- a/gpu/gles2_conform_support/egl/context.cc
+++ b/gpu/gles2_conform_support/egl/context.cc
@@ -181,6 +181,11 @@ int32_t Context::CreateGpuMemoryBufferImage(size_t width,
   return -1;
 }
 
+int32_t Context::GetImageGpuMemoryBufferId(unsigned image_id) {
+  NOTIMPLEMENTED();
+  return -1;
+}
+
 void Context::SignalQuery(uint32_t query, const base::Closure& callback) {
   NOTIMPLEMENTED();
 }