command_buffer: Implement path rendering functions for CHROMIUM_path_rendering

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 c747383ee818f090e2d061493253a1a784ade3d3..72b72ff7ae499891ff8ae810f966743872af0444 100644
--- a/gpu/command_buffer/service/feature_info.cc
+++ b/gpu/command_buffer/service/feature_info.cc
@@ -209,6 +209,9 @@ void FeatureInfo::InitializeBasicState(const base::CommandLine& command_line) {
   enable_unsafe_es3_apis_switch_ =
       command_line.HasSwitch(switches::kEnableUnsafeES3APIs);
 
+  enable_gl_path_rendering_switch_ =
+      command_line.HasSwitch(switches::kEnableGLPathRendering);
+
   unsafe_es3_apis_enabled_ = false;
 }
 
@@ -1004,13 +1007,17 @@ void FeatureInfo::InitializeFeatures() {
     }
   }
 
-  if (extensions.Contains("GL_NV_path_rendering")) {
+  if (enable_gl_path_rendering_switch_ &&
+      extensions.Contains("GL_NV_path_rendering")) {
     if (extensions.Contains("GL_EXT_direct_state_access") ||
         gl_version_info_->is_es3) {
       AddExtensionString("GL_CHROMIUM_path_rendering");
       feature_flags_.chromium_path_rendering = true;
       validators_.g_l_state.AddValue(GL_PATH_MODELVIEW_MATRIX_CHROMIUM);
       validators_.g_l_state.AddValue(GL_PATH_PROJECTION_MATRIX_CHROMIUM);
+      validators_.g_l_state.AddValue(GL_PATH_STENCIL_FUNC_CHROMIUM);
+      validators_.g_l_state.AddValue(GL_PATH_STENCIL_REF_CHROMIUM);
+      validators_.g_l_state.AddValue(GL_PATH_STENCIL_VALUE_MASK_CHROMIUM);
     }
   }