gpu: Add Serialize function to ContextCreationAttribParser.

gpu/command_buffer/common/gles2_cmd_utils.h

Index: gpu/command_buffer/common/gles2_cmd_utils.h
diff --git a/gpu/command_buffer/common/gles2_cmd_utils.h b/gpu/command_buffer/common/gles2_cmd_utils.h
index 4bc4b1b7fcc237f621285e6464f02b3258eb0517..b8619e61d3785dc4a619e4824faa34468defae08 100644
--- a/gpu/command_buffer/common/gles2_cmd_utils.h
+++ b/gpu/command_buffer/common/gles2_cmd_utils.h
@@ -174,9 +174,11 @@ class GLES2_UTILS_EXPORT GLES2Util {
   int num_shader_binary_formats_;
 };
 
-class GLES2_UTILS_EXPORT ContextCreationAttribParser {
+class GLES2_UTILS_EXPORT ContextCreationAttribHelper {
  public:
-  ContextCreationAttribParser();
+  ContextCreationAttribHelper();
+
+  void Serialize(std::vector<int32>* attribs);
   bool Parse(const std::vector<int32>& attribs);
 
   // -1 if invalid or unspecified.