Service Worker: Add a timeout error value.

Source/modules/serviceworkers/ServiceWorkerError.cpp

Index: Source/modules/serviceworkers/ServiceWorkerError.cpp
diff --git a/Source/modules/serviceworkers/ServiceWorkerError.cpp b/Source/modules/serviceworkers/ServiceWorkerError.cpp
index 313f2a866d3909857de4b4852f951e708479d731..09f735fdf02bf740818d7c82e5e0c73fb18e2c84 100644
--- a/Source/modules/serviceworkers/ServiceWorkerError.cpp
+++ b/Source/modules/serviceworkers/ServiceWorkerError.cpp
@@ -67,6 +67,8 @@ PassRefPtrWillBeRawPtr<DOMException> ServiceWorkerError::take(ScriptPromiseResol
         return createException(SecurityError, "The Service Worker security policy prevented an action.", webError->message);
     case WebServiceWorkerError::ErrorTypeState:
         return createException(InvalidStateError, "The Service Worker state was not valid.", webError->message);
+    case WebServiceWorkerError::ErrorTypeTimeout:
+        return createException(AbortError, "The Service Worker operation timed out.", webError->message);
     case WebServiceWorkerError::ErrorTypeUnknown:
         return createException(UnknownError, "An unknown error occurred within Service Worker.", webError->message);
     }