Add FeatureList plumbing for the LazyParseCSS experiment

content/public/common/content_features.cc

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "build/build_config.h"
 #include "content/public/common/content_features.h"
 
 namespace features {
 
 // All features in alphabetical order.
@@ skipping 64 matching lines @@
 
 // Enables extended Gamepad API features like motion tracking and haptics.
 const base::Feature kGamepadExtensions{"GamepadExtensions",
                                        base::FEATURE_DISABLED_BY_DEFAULT};
 
 // Enables sensors based on Generic Sensor API:
 // https://w3c.github.io/sensors/
 const base::Feature kGenericSensor{"GenericSensor",
                                    base::FEATURE_DISABLED_BY_DEFAULT};
 
+// Enables lazily parsing css properties for performance.
+const base::Feature kLazyParseCSS{"LazyParseCSS",
+                                  base::FEATURE_DISABLED_BY_DEFAULT};
 
 // FeatureList definition for trials to enable the download button on
 // MediaDocument.
 const base::Feature kMediaDocumentDownloadButton{
     "MediaDocumentDownloadButton",
     base::FEATURE_DISABLED_BY_DEFAULT
 };
 
 // Enables the memory coordinator.
 // WARNING:
@@ skipping 144 matching lines @@
 #endif
 
 #if defined(OS_WIN)
 // Emergency "off switch" for new Windows sandbox security mitigation,
 // sandbox::MITIGATION_EXTENSION_POINT_DISABLE.
 const base::Feature kWinSboxDisableExtensionPoints{
     "WinSboxDisableExtensionPoint", base::FEATURE_ENABLED_BY_DEFAULT};
 #endif
 
 }  // namespace features