ServiceWorker, remove old Cache API implementation to make way for the polyfill.

Source/modules/serviceworkers/Cache.idl

Index: Source/modules/serviceworkers/Cache.idl
diff --git a/Source/modules/serviceworkers/Cache.idl b/Source/modules/serviceworkers/Cache.idl
deleted file mode 100644
index 567c5e985b2d9d37733254b3bde513e9b1027086..0000000000000000000000000000000000000000
--- a/Source/modules/serviceworkers/Cache.idl
+++ /dev/null
@@ -1,12 +0,0 @@
-// Copyright 2014 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-[
-    Constructor(DOMString[] urls),
-    Exposed=ServiceWorker,
-    RuntimeEnabled=ServiceWorker
-] interface Cache {
-    [CallWith=ScriptState] Promise match(DOMString url);
-    [CallWith=ScriptState] Promise ready();
-};