Remove the unused source_process_id and provider_host arguments to SW unregistration.

content/public/browser/service_worker_context.h

Index: content/public/browser/service_worker_context.h
diff --git a/content/public/browser/service_worker_context.h b/content/public/browser/service_worker_context.h
index 57aa955b33c75967201e005abb0d1c9f9dfc9164..a701d6c7a56176168fc9593f05c025d2cea70db7 100644
--- a/content/public/browser/service_worker_context.h
+++ b/content/public/browser/service_worker_context.h
@@ -37,15 +37,14 @@ class ServiceWorkerContext {
                                      const ResultCallback& callback) = 0;
 
   // Equivalent to calling navigator.serviceWorker.unregister(pattern) from a
-  // renderer in |source_process_id|, except that |pattern| is an absolute URL
-  // instead of relative to some current origin.  |callback| is passed true
-  // when the JS promise is fulfilled or false when the JS promise is rejected.
+  // renderer, except that |pattern| is an absolute URL instead of relative to
+  // some current origin.  |callback| is passed true when the JS promise is
+  // fulfilled or false when the JS promise is rejected.
   //
   // Unregistration can fail if:
   //  * No Service Worker was registered for |pattern|.
   //  * Something unexpected goes wrong, like a renderer crash.
   virtual void UnregisterServiceWorker(const Scope& pattern,
-                                       int source_process_id,
                                        const ResultCallback& callback) = 0;
 
   // TODO(jyasskin): Provide a way to SendMessage to a Scope.