Add a feature for not compositing small scrollers

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 125 matching lines @@
     "MediaStreamOldVideoConstraints", base::FEATURE_DISABLED_BY_DEFAULT};
 
 // Enables the memory coordinator.
 // WARNING:
 // The memory coordinator is not ready for use and enabling this may cause
 // unexpected memory regression at this point. Please do not enable this.
 const base::Feature kMemoryCoordinator {
   "MemoryCoordinator", base::FEATURE_DISABLED_BY_DEFAULT
 };
 
+// An experiment for not compositing small scrollers.
+const base::Feature kNotCompositeSmallScroller{
+    "kNotCompositeSmallScroller", base::FEATURE_DISABLED_BY_DEFAULT};

[jwd, 2017/06/02 18:27:35]

Nit: Don't include the k in the string name of the feature.

[jwd, 2017/06/02 18:27:35]

Nit: Add a newline after this.

[yigu, 2017/06/02 18:39:02]

Done.

 // Kill switch for Web Notification content images.
 const base::Feature kNotificationContentImage{"NotificationContentImage",
                                               base::FEATURE_ENABLED_BY_DEFAULT};
 // An experiment forcing events to be non-blocking when the main thread is
 // deemed unresponsive.  See crbug.com/599609.
 const base::Feature kMainThreadBusyScrollIntervention{
     "MainThreadBusyScrollIntervention", base::FEATURE_DISABLED_BY_DEFAULT};
 
 // Experimental resource fetch optimizations for workers. See crbug.com/443374
 const base::Feature kOffMainThreadFetch{"OffMainThreadFetch",
@@ skipping 204 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