Make sure gin Handles exist before using them

chrome/renderer/net/net_error_page_controller.cc

Index: chrome/renderer/net/net_error_page_controller.cc
diff --git a/chrome/renderer/net/net_error_page_controller.cc b/chrome/renderer/net/net_error_page_controller.cc
index 66ca54f511d5674ec218549b510a1ea47bb21a0b..81756d665f0e000090d453a8555f66cf0e2906d9 100644
--- a/chrome/renderer/net/net_error_page_controller.cc
+++ b/chrome/renderer/net/net_error_page_controller.cc
@@ -28,6 +28,9 @@ void NetErrorPageController::Install(content::RenderFrame* render_frame) {
 
   gin::Handle<NetErrorPageController> controller = gin::CreateHandle(
       isolate, new NetErrorPageController(render_frame));
+  if (controller.IsEmpty())
+    return;
+
   v8::Handle<v8::Object> global = context->Global();
   global->Set(gin::StringToV8(isolate, "errorPageController"),
               controller.ToV8());