Introduce ActiveScriptController; track active extension scripts

extensions/common/feature_switch.cc

Index: extensions/common/feature_switch.cc
diff --git a/extensions/common/feature_switch.cc b/extensions/common/feature_switch.cc
index 91ebdda9a05f73b301ac1de9f7ee445781950ee5..121dceb25ce89b7efb04f8e5cdde4e4dd52a1ada 100644
--- a/extensions/common/feature_switch.cc
+++ b/extensions/common/feature_switch.cc
@@ -42,7 +42,9 @@ class CommonSwitches {
             FeatureSwitch::DEFAULT_DISABLED),
         enable_override_bookmarks_ui(
             switches::kEnableOverrideBookmarksUI,
-            FeatureSwitch::DEFAULT_DISABLED) {}
+            FeatureSwitch::DEFAULT_DISABLED),
+        scripts_require_action(switches::kScriptsRequireAction,
+                               FeatureSwitch::DEFAULT_DISABLED) {}
 
   // Enables extensions to be easily installed from sites other than the web
   // store.
@@ -57,6 +59,7 @@ class CommonSwitches {
 
   FeatureSwitch error_console;
   FeatureSwitch enable_override_bookmarks_ui;
+  FeatureSwitch scripts_require_action;
 };
 
 base::LazyInstance<CommonSwitches> g_common_switches =
@@ -83,6 +86,10 @@ FeatureSwitch* FeatureSwitch::enable_override_bookmarks_ui() {
   return &g_common_switches.Get().enable_override_bookmarks_ui;
 }
 
+FeatureSwitch* FeatureSwitch::scripts_require_action() {
+  return &g_common_switches.Get().scripts_require_action;
+}
+
 FeatureSwitch::ScopedOverride::ScopedOverride(FeatureSwitch* feature,
                                               bool override_value)
     : feature_(feature),