Add mouse input forwarding to gpu service

gpu/command_buffer/service/feature_info.cc

Index: gpu/command_buffer/service/feature_info.cc
diff --git a/gpu/command_buffer/service/feature_info.cc b/gpu/command_buffer/service/feature_info.cc
index 6dd1f34f1ee8c63a508a52bf0613977ca0279e96..b67ca2f7807b0d12db0cee62211d860bac4f2ac4 100644
--- a/gpu/command_buffer/service/feature_info.cc
+++ b/gpu/command_buffer/service/feature_info.cc
@@ -145,7 +145,8 @@ FeatureInfo::FeatureFlags::FeatureFlags()
       ext_texture_storage(false),
       chromium_path_rendering(false),
       blend_equation_advanced(false),
-      blend_equation_advanced_coherent(false) {
+      blend_equation_advanced_coherent(false),
+      enable_subscribe_uniform(false) {
 }
 
 FeatureInfo::Workarounds::Workarounds() :
@@ -179,6 +180,9 @@ void FeatureInfo::InitializeBasicState(const CommandLine& command_line) {
   feature_flags_.is_swiftshader =
       (command_line.GetSwitchValueASCII(switches::kUseGL) == "swiftshader");
 
+  feature_flags_.enable_subscribe_uniform =
+      command_line.HasSwitch(switches::kEnableSubscribeUniformExtension);
+
   static const GLenum kAlphaTypes[] = {
       GL_UNSIGNED_BYTE,
   };
@@ -261,6 +265,10 @@ void FeatureInfo::InitializeFeatures() {
   AddExtensionString("GL_CHROMIUM_texture_mailbox");
   AddExtensionString("GL_EXT_debug_marker");
 
+  if (feature_flags_.enable_subscribe_uniform) {
+    AddExtensionString("GL_CHROMIUM_subscribe_uniform");
+  }
+
   // OES_vertex_array_object is emulated if not present natively,
   // so the extension string is always exposed.
   AddExtensionString("GL_OES_vertex_array_object");