gpu: Implement GL_INTEL_framebuffer_CMAA via shaders in the GPU Service

gpu/command_buffer/service/feature_info.h

Index: gpu/command_buffer/service/feature_info.h
diff --git a/gpu/command_buffer/service/feature_info.h b/gpu/command_buffer/service/feature_info.h
index ff6b354d1fa13772042ba37839372aab0e1a5d57..c8ea959f2b5415af30ed226c97f3781ab003d1d3 100644
--- a/gpu/command_buffer/service/feature_info.h
+++ b/gpu/command_buffer/service/feature_info.h
@@ -42,6 +42,7 @@ class GPU_EXPORT FeatureInfo : public base::RefCounted<FeatureInfo> {
     // Use the IMG GLenum values and functions rather than EXT.
     bool use_img_for_multisampled_render_to_texture;
     bool chromium_screen_space_antialiasing;
+    bool use_chromium_screen_space_antialiasing_via_shaders;
     bool oes_standard_derivatives;
     bool oes_egl_image_external;
     bool nv_egl_stream_consumer_external;
@@ -191,6 +192,9 @@ class GPU_EXPORT FeatureInfo : public base::RefCounted<FeatureInfo> {
   bool disable_shader_translator_;
   std::unique_ptr<gl::GLVersionInfo> gl_version_info_;
 
+  // Whether the command line switch kEnableCMAAShaders is passed in.
+  bool enable_cmaa_shaders_switch_;
+
   DISALLOW_COPY_AND_ASSIGN(FeatureInfo);
 };