Improve CopyTex{Sub}Image2D format validation.

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 a6e8bcb4770f5804b341c5670d16ac53643aa948..bae6768d13a3a47f1cec6e6430bde698bc128e33 100644
--- a/gpu/command_buffer/common/gles2_cmd_utils.h
+++ b/gpu/command_buffer/common/gles2_cmd_utils.h
@@ -239,6 +239,10 @@ class GLES2_UTILS_EXPORT GLES2Util {
   static bool IsIntegerFormat(uint32_t internal_format);
   static bool IsFloatFormat(uint32_t internal_format);
 
+  static bool IsSizedColorFormat(uint32_t internal_format);
+  static void GetColorFormatComponentSizes(
+      uint32_t internal_format, uint32_t type, int* r, int* g, int* b, int* a);
+
   // Computes the data size for certain gl commands like glUniform.
   static bool ComputeDataSize(uint32_t count,
                               size_t size,