[Extensions] Add an access check before executing native code in the renderer

extensions/renderer/user_gestures_native_handler.cc

Index: extensions/renderer/user_gestures_native_handler.cc
diff --git a/extensions/renderer/user_gestures_native_handler.cc b/extensions/renderer/user_gestures_native_handler.cc
index 852762c0e2c3db1197b2304dfdcbe954f819b952..c01a4ae7240532a1ca11e8174f9448834b07a1e9 100644
--- a/extensions/renderer/user_gestures_native_handler.cc
+++ b/extensions/renderer/user_gestures_native_handler.cc
@@ -14,12 +14,15 @@ namespace extensions {
 UserGesturesNativeHandler::UserGesturesNativeHandler(ScriptContext* context)
     : ObjectBackedNativeHandler(context) {
   RouteFunction("IsProcessingUserGesture",
+                "test",

[Devlin, 2016/03/30 22:02:28]

Ideally, we'd be able to attribute all the native handlers to a particular API
in order to perform this check.  We can go through and update them piecemeal if
this lgty.

                 base::Bind(&UserGesturesNativeHandler::IsProcessingUserGesture,
                            base::Unretained(this)));
   RouteFunction("RunWithUserGesture",
+                "test",
                 base::Bind(&UserGesturesNativeHandler::RunWithUserGesture,
                            base::Unretained(this)));
   RouteFunction("RunWithoutUserGesture",
+                "test",
                 base::Bind(&UserGesturesNativeHandler::RunWithoutUserGesture,
                            base::Unretained(this)));
 }