Plumb through EGL_NV_post_sub_buffer and GLX_MESA_copy_sub_buffer.

gpu/command_buffer/service/gles2_cmd_decoder.cc

Index: gpu/command_buffer/service/gles2_cmd_decoder.cc
diff --git a/gpu/command_buffer/service/gles2_cmd_decoder.cc b/gpu/command_buffer/service/gles2_cmd_decoder.cc
index 3fc8f2791be3176da7ca0d2f5288078182ad0022..7785a056b7e61c40da79600b01f50d833c6706da 100644
--- a/gpu/command_buffer/service/gles2_cmd_decoder.cc
+++ b/gpu/command_buffer/service/gles2_cmd_decoder.cc
@@ -5677,6 +5677,16 @@ error::Error GLES2DecoderImpl::HandlePixelStorei(
   return error::kNoError;
 }
 
+error::Error GLES2DecoderImpl::HandlePostSubBufferCHROMIUM(
+    uint32 immediate_data_size, const gles2::PostSubBufferCHROMIUM& c) {
+  DCHECK(surface_->SupportsPostSubBuffer());
+  TRACE_EVENT0("gpu", "GLES2DecoderImpl::HandlePostSubBufferCHROMIUM");
+  if (surface_->PostSubBuffer(c.x, c.y, c.width, c.height))
+    return error::kLostContext;
+  else
+    return error::kNoError;
+}
+
 error::Error GLES2DecoderImpl::GetAttribLocationHelper(
     GLuint client_id, uint32 location_shm_id, uint32 location_shm_offset,
     const std::string& name_str) {