Add a webstore API for installing bundles of extensions.

chrome/test/data/extensions/api_test/webstore_private/common.js

Index: chrome/test/data/extensions/api_test/webstore_private/common.js
diff --git a/chrome/test/data/extensions/api_test/webstore_private/common.js b/chrome/test/data/extensions/api_test/webstore_private/common.js
index 17025a42bebc09fd2291355c05e466cdfa9d3165..620f2b3d06054d44d9595c2a70636e923ada4ac5 100644
--- a/chrome/test/data/extensions/api_test/webstore_private/common.js
+++ b/chrome/test/data/extensions/api_test/webstore_private/common.js
@@ -9,6 +9,7 @@ var extensionId = "enfkhcelefdadlmkffamgdlgplcionje";
 var appId = "iladmdjkfniedhfhcfoefgojhgaiaccc";
 
 var assertEq = chrome.test.assertEq;
+var assertFalse = chrome.test.assertFalse;
 var assertNoLastError = chrome.test.assertNoLastError;
 var assertTrue = chrome.test.assertTrue;
 var callbackFail = chrome.test.callbackFail;
@@ -58,13 +59,8 @@ function getIconData(callback) {
   img.src = "extension/icon.png";
 }
 
-var cachedManifest = null;
-
 // This returns the string contents of the extension's manifest file.
 function getManifest(alternativePath) {
-  if (cachedManifest)
-    return cachedManifest;
-
   // Do a synchronous XHR to get the manifest.
   var xhr = new XMLHttpRequest();
   xhr.open("GET",