WebVR: implement SetSurfaceHandleCHROMIUM extension for gvr_device.

gpu/command_buffer/build_gles2_cmd_buffer.py

Index: gpu/command_buffer/build_gles2_cmd_buffer.py
diff --git a/gpu/command_buffer/build_gles2_cmd_buffer.py b/gpu/command_buffer/build_gles2_cmd_buffer.py
index 49518430b545ed91b835d9c2168106ed3692ba2b..0968a35fded33783917f1c3c442b953448cf3938 100755
--- a/gpu/command_buffer/build_gles2_cmd_buffer.py
+++ b/gpu/command_buffer/build_gles2_cmd_buffer.py
@@ -3599,6 +3599,13 @@ _FUNCTION_INFO = {
     'first_element_only': True,
     'es3': True,
   },
+  'SetSurfaceHandleCHROMIUM': {
+    'decoder_func': 'DoSetSurfaceHandleCHROMIUM',
+    'unit_test': False,
+    'client_test': False,
+    'chromium': True,
+    'extension': True,

[piman, 2016/11/09 17:50:06]

A new extension should have a name and documentation in
gpu/GLES2/extensions/CHROMIUM/
We also need to expose it in the extension list, using AddExtensionString in
FeatureInfo::InitializeFeatures, so that the client can know whether it's
available or not. Additionally, you may consider adding a bool to
gpu::Capabilities, so that the client can save a round-trip to check for
availability. Lastly, you can consider adding a bool to
FeatureInfo::FeatureFlags, and referencing its name here as 'extension_flag' so
that the auto-generator can generate checking for availability of that
extension.

+  },
   'ShaderBinary': {
     'type': 'Custom',
     'client_test': False,