Make sure gin Handles exist before using them

content/shell/renderer/test_runner/test_runner.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/shell/renderer/test_runner/test_runner.h"
 
 #include <limits>
 
 #include "base/logging.h"
 #include "content/shell/common/test_runner/test_preferences.h"
@@ skipping 266 matching lines @@
   v8::Isolate* isolate = blink::mainThreadIsolate();
   v8::HandleScope handle_scope(isolate);
   v8::Handle<v8::Context> context = frame->mainWorldScriptContext();
   if (context.IsEmpty())
     return;
 
   v8::Context::Scope context_scope(context);
 
   gin::Handle<TestRunnerBindings> bindings =
       gin::CreateHandle(isolate, new TestRunnerBindings(runner));
+  if (bindings.IsEmpty())
+    return;
   v8::Handle<v8::Object> global = context->Global();
   v8::Handle<v8::Value> v8_bindings = bindings.ToV8();
   global->Set(gin::StringToV8(isolate, "testRunner"), v8_bindings);
   global->Set(gin::StringToV8(isolate, "layoutTestController"), v8_bindings);
 }
 
 TestRunnerBindings::TestRunnerBindings(base::WeakPtr<TestRunner> runner)
     : runner_(runner) {}
 
 TestRunnerBindings::~TestRunnerBindings() {}
@@ skipping 2343 matching lines @@
 }
 
 void TestRunner::DidLosePointerLockInternal() {
   bool was_locked = pointer_locked_;
   pointer_locked_ = false;
   if (was_locked)
     web_view_->didLosePointerLock();
 }
 
 }  // namespace content