[mojo] Enable ServiceRegistryImpl to override remote services

content/renderer/mojo/service_registry_js_wrapper.h

Index: content/renderer/mojo/service_registry_js_wrapper.h
diff --git a/content/renderer/mojo/service_registry_js_wrapper.h b/content/renderer/mojo/service_registry_js_wrapper.h
index 73046862dbbe26e70bc01dc5c98be50f1cd757e6..543d214c109dfb3588cace09b408d9a2d35e45b6 100644
--- a/content/renderer/mojo/service_registry_js_wrapper.h
+++ b/content/renderer/mojo/service_registry_js_wrapper.h
@@ -12,7 +12,11 @@
 #include "gin/handle.h"
 #include "gin/object_template_builder.h"
 #include "gin/wrappable.h"
-#include "mojo/public/cpp/system/core.h"
+#include "mojo/public/cpp/system/handle.h"
+
+namespace v8 {
+class Isolate;
+}
 
 namespace content {
 
@@ -33,6 +37,8 @@ class CONTENT_EXPORT ServiceRegistryJsWrapper
       v8::Isolate* isolate) override;
 
   // JS interface implementation.
+  void AddServiceOverrideForTesting(const std::string& service_name,
+                                    v8::Local<v8::Function> service_factory);
   mojo::Handle ConnectToService(const std::string& service_name);
 
   static gin::WrapperInfo kWrapperInfo;