ui: Cleanup class/struct forward declarations

extensions/renderer/guest_view/guest_view_internal_custom_bindings.cc

Index: extensions/renderer/guest_view/guest_view_internal_custom_bindings.cc
diff --git a/extensions/renderer/guest_view/guest_view_internal_custom_bindings.cc b/extensions/renderer/guest_view/guest_view_internal_custom_bindings.cc
index 021636e1d5dfbde01bc6ec4cfad54a96743cc05a..bec7d1c852016119b6a3df2e7c81ffbda0047867 100644
--- a/extensions/renderer/guest_view/guest_view_internal_custom_bindings.cc
+++ b/extensions/renderer/guest_view/guest_view_internal_custom_bindings.cc
@@ -427,11 +427,14 @@ void GuestViewInternalCustomBindings::RegisterView(
 void GuestViewInternalCustomBindings::RunWithGesture(
     const v8::FunctionCallbackInfo<v8::Value>& args) {
   // Gesture is required to request fullscreen.
+  // TODO(devlin): All this needs to do is enter fullscreen. We should make this
+  // EnterFullscreen() and do it directly rather than having a generic "run with
+  // user gesture" function.
   blink::WebScopedUserGesture user_gesture(context()->web_frame());
   CHECK_EQ(args.Length(), 1);
   CHECK(args[0]->IsFunction());
-  v8::Local<v8::Value> no_args;
-  context()->CallFunction(v8::Local<v8::Function>::Cast(args[0]), 0, &no_args);
+  context()->SafeCallFunction(
+      v8::Local<v8::Function>::Cast(args[0]), 0, nullptr);
 }
 
 }  // namespace extensions