Make all quota-exceeding messages in the storage API explain what the failure

chrome/test/data/extensions/api_test/settings/simple_test/background.js

 // Copyright (c) 2012 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.
 
 function test(stage0) {
   var apis = [
     chrome.storage.sync,
     chrome.storage.local
   ];
   apis.forEach(function(api) {
@@ skipping 338 matching lines @@
       } else {
         area.clear(function() {
           clearNTimes(area, n - 1, whenDone);
         });
       }
     }
 
     var local = chrome.storage.local;
     var sync = chrome.storage.sync;
     var test = chrome.test;
-    var quotaError = "This request exceeds available quota.";
+    var quotaError =
+        "This request exceeds the MAX_WRITE_OPERATIONS_PER_HOUR quota.";
 
     clearNTimes(local, 1001, test.callbackPass(function() {
       clearNTimes(sync, 1001, test.callbackFail(quotaError, function() {
         clearNTimes(local, 1, test.callbackPass(function() {
           clearNTimes(sync, 1, test.callbackFail(quotaError, test.succeed));
         }));
       }));
     }));
   }
 ]);