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

content/renderer/renderer_blink_platform_impl.h

Index: content/renderer/renderer_blink_platform_impl.h
diff --git a/content/renderer/renderer_blink_platform_impl.h b/content/renderer/renderer_blink_platform_impl.h
index 6c9ac6633ab6de62f4c152cdc8d325c2766a887a..fcb2360d8eed2b1515c0a12c8e3d34e444e78085 100644
--- a/content/renderer/renderer_blink_platform_impl.h
+++ b/content/renderer/renderer_blink_platform_impl.h
@@ -49,6 +49,7 @@ class InterfaceProvider;
 }
 
 namespace content {
+class BlinkConnectorImpl;
 class BlinkInterfaceProviderImpl;
 class LocalStorageCachedAreas;
 class PlatformEventObserverBase;
@@ -183,6 +184,7 @@ class CONTENT_EXPORT RendererBlinkPlatformImpl : public BlinkPlatformImpl {
       const blink::WebSize& size) override;
   blink::WebCompositorSupport* compositorSupport() override;
   blink::WebString convertIDNToUnicode(const blink::WebString& host) override;
+  blink::Connector* connector() override;
   blink::InterfaceProvider* interfaceProvider() override;
   void startListening(blink::WebPlatformEventType,
                       blink::WebPlatformEventListener*) override;
@@ -294,6 +296,8 @@ class CONTENT_EXPORT RendererBlinkPlatformImpl : public BlinkPlatformImpl {
 
   std::unique_ptr<LocalStorageCachedAreas> local_storage_cached_areas_;
 
+  std::unique_ptr<BlinkConnectorImpl> blink_connector_;
+
   std::unique_ptr<BlinkInterfaceProviderImpl> blink_interface_provider_;
 
   mojom::URLLoaderFactoryAssociatedPtr url_loader_factory_;