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 ed0ddc95fdac9171ab6fce61144b33c86ce67eb3..9fec2e106fa9864a076840741e4ff2851cf45cb3 100644
--- a/gpu/command_buffer/service/feature_info.cc
+++ b/gpu/command_buffer/service/feature_info.cc
@@ -146,7 +146,8 @@ FeatureInfo::FeatureFlags::FeatureFlags()
       chromium_path_rendering(false),
       blend_equation_advanced(false),
       blend_equation_advanced_coherent(false),
-      ext_texture_rg(false) {
+      ext_texture_rg(false),
+      enable_subscribe_uniform(false) {
 }
 
 FeatureInfo::Workarounds::Workarounds() :
@@ -180,6 +181,9 @@ 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,
   };
@@ -295,6 +299,10 @@ 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");