Start implementing ForeignFetchEvent for foreign fetch events.

third_party/WebKit/Source/modules/serviceworkers/RespondWithObserver.cpp

Index: third_party/WebKit/Source/modules/serviceworkers/RespondWithObserver.cpp
diff --git a/third_party/WebKit/Source/modules/serviceworkers/RespondWithObserver.cpp b/third_party/WebKit/Source/modules/serviceworkers/RespondWithObserver.cpp
index 5c3f91db12dac60622b0a8ba249658976f35e23c..065190347620891fab3988ed7a37f12351204a92 100644
--- a/third_party/WebKit/Source/modules/serviceworkers/RespondWithObserver.cpp
+++ b/third_party/WebKit/Source/modules/serviceworkers/RespondWithObserver.cpp
@@ -59,6 +59,9 @@ const String getMessageForResponseError(WebServiceWorkerResponseError error, con
     case WebServiceWorkerResponseErrorBodyLocked:
         errorMessage = errorMessage + "a Response whose \"body\" is locked cannot be used to respond to a request.";
         break;
+    case WebServiceWorkerResponseErrorNoForeignFetchResponse:
+        errorMessage = errorMessage + "an object that was not a ForeignFetchResponse was passed to respondWith().";
+        break;
     case WebServiceWorkerResponseErrorUnknown:
     default:
         errorMessage = errorMessage + "an unexpected error occurred.";
@@ -134,6 +137,8 @@ private:
     ResolveType m_resolveType;
 };
 
+RespondWithObserver::~RespondWithObserver() {}
+
 RespondWithObserver* RespondWithObserver::create(ExecutionContext* context, int eventID, const KURL& requestURL, WebURLRequest::FetchRequestMode requestMode, WebURLRequest::FrameType frameType, WebURLRequest::RequestContext requestContext)
 {
     return new RespondWithObserver(context, eventID, requestURL, requestMode, frameType, requestContext);