Allow creating GLImage-backed textures with glTexStorage2D.

gpu/command_buffer/common/capabilities.h

Index: gpu/command_buffer/common/capabilities.h
diff --git a/gpu/command_buffer/common/capabilities.h b/gpu/command_buffer/common/capabilities.h
index 0ac1136b7f6a6a4294cb73d00c065af6af998010..2ad1bfbe26172256755964a3abbb0f9ac8971403 100644
--- a/gpu/command_buffer/common/capabilities.h
+++ b/gpu/command_buffer/common/capabilities.h
@@ -179,6 +179,9 @@ struct GPU_EXPORT Capabilities {
   // When true, non-empty post sub buffer calls are unsupported.
   bool disable_non_empty_post_sub_buffers = false;
 
+  // Use GL_CHROMIUM_texture_buffer extension if true.
+  bool texture_buffer_chromium = false;

[dcheng1, 2017/08/09 09:58:57]

Nit: I would personally prefix this with use_ to be consistent with the other
bool flags used for this.

+
   int major_version = 2;
   int minor_version = 0;
 };