Refactor Blink's ServiceConnector and add ability to mock in layout tests

third_party/WebKit/Source/platform/exported/ServiceRegistry.cpp

 // Copyright 2016 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 "public/platform/Connector.h"
 #include "public/platform/InterfaceProvider.h"
 
 #include "wtf/StdLibExtras.h"
 
 namespace blink {
 namespace {
 
+class EmptyConnector : public Connector {
+  void bindInterface(const char* serviceName,
+                     const char* interfaceName,
+                     mojo::ScopedMessagePipeHandle) override {}
+};
+
 class EmptyInterfaceProvider : public InterfaceProvider {
   void getInterface(const char* name, mojo::ScopedMessagePipeHandle) override {}
 };
 }
 
+Connector* Connector::getEmptyConnector() {
+  DEFINE_STATIC_LOCAL(EmptyConnector, emptyConnector, ());
+  return &emptyConnector;
+}
+
 InterfaceProvider* InterfaceProvider::getEmptyInterfaceProvider() {
   DEFINE_STATIC_LOCAL(EmptyInterfaceProvider, emptyInterfaceProvider, ());
   return &emptyInterfaceProvider;
 }
 }