Plugin Power Saver: Add flag to experiment behind.

content/public/common/content_switches.cc

Index: content/public/common/content_switches.cc
diff --git a/content/public/common/content_switches.cc b/content/public/common/content_switches.cc
index 5e04c9dcfbec7508fa6be27c321a9398a8c90183..d063e5c0fabf9a7215135608bcc403346d165e50 100644
--- a/content/public/common/content_switches.cc
+++ b/content/public/common/content_switches.cc
@@ -395,6 +395,9 @@ const char kEnableOverscrollNotifications[] = "enable-overscroll-notifications";
 // Enables compositor-accelerated touch-screen pinch gestures.
 const char kEnablePinch[]                   = "enable-pinch";
 
+// Enables the plugin power saver feature.
+const char kEnablePluginPowerSaver[]        = "enable-plugin-power-saver";
+
 // Make the values returned to window.performance.memory more granular and more
 // up to date in shared worker. Without this flag, the memory information is
 // still available, but it is bucketized and updated less frequently. This flag