<webview> Implement clear http cache API.

chrome/test/data/extensions/platform_apps/web_view/clear_data_cache/guest.js

Index: chrome/test/data/extensions/platform_apps/web_view/clear_data_cache/guest.js
diff --git a/chrome/test/data/extensions/platform_apps/web_view/common/useragent/guest.js b/chrome/test/data/extensions/platform_apps/web_view/clear_data_cache/guest.js
similarity index 62%
copy from chrome/test/data/extensions/platform_apps/web_view/common/useragent/guest.js
copy to chrome/test/data/extensions/platform_apps/web_view/clear_data_cache/guest.js
index 64eb9f548e4c46ce96b4a28fd8fec6df6ed0d092..6b90df3fabbf1d16cf71503ae8e3fe6e4a24e77d 100644
--- a/chrome/test/data/extensions/platform_apps/web_view/common/useragent/guest.js
+++ b/chrome/test/data/extensions/platform_apps/web_view/clear_data_cache/guest.js
@@ -1,8 +1,9 @@
-// Copyright 2013 The Chromium Authors. All rights reserved.
+// Copyright 2015 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.
 
-window.console.log('Guest script loading.');
+var LOG = function(msg) { window.console.log(msg); };
+LOG('Guest script loading.');
 
 // The window reference of the embedder to send post message reply.
 var embedderWindowChannel = null;
@@ -18,20 +19,10 @@ var notifyEmbedder = function(msg_array) {
 var onPostMessageReceived = function(e) {
   embedderWindowChannel = e.source;
   var data = JSON.parse(e.data);
-  if (data[0] == 'create-channel') {
+  if (data[0] == 'connect') {
     channelId = data[1];
-    notifyEmbedder(['channel-created']);
+    notifyEmbedder(['connected']);
     return;
   }
-
-  // Tests.
-  // These logs trigger event listeners in the embedder.
-  switch (data[0]) {
-    case 'get-user-agent':
-      notifyEmbedder(['got-user-agent', navigator.userAgent]);
-      break;
-    default:
-      break;
-  }
 };
 window.addEventListener('message', onPostMessageReceived, false);