[ServiceWorker] Set FetchRequestMode and handle wasFetchedViaServiceWorker.

Source/core/fetch/FetchRequest.cpp

Index: Source/core/fetch/FetchRequest.cpp
diff --git a/Source/core/fetch/FetchRequest.cpp b/Source/core/fetch/FetchRequest.cpp
index 5962054a5eb5ddc2193545b4941d31ee605a8f40..8c0e84c609aa78841449303dbe607692ecfc30e2 100644
--- a/Source/core/fetch/FetchRequest.cpp
+++ b/Source/core/fetch/FetchRequest.cpp
@@ -72,6 +72,7 @@ FetchRequest::~FetchRequest()
 void FetchRequest::setCrossOriginAccessControl(SecurityOrigin* origin, StoredCredentials allowCredentials, CredentialRequest requested)
 {
     ASSERT(requested == ClientDidNotRequestCredentials || allowCredentials == AllowStoredCredentials);
+    m_resourceRequest.setFetchRequestMode(WebURLRequest::FetchRequestModeCORS);
     updateRequestForAccessControl(m_resourceRequest, origin, allowCredentials);
     m_options.allowCredentials = allowCredentials;
     m_options.corsEnabled = IsCORSEnabled;