Keep browser process alive while there are platform apps with background pages running.

chrome/browser/extensions/extension_apitest.h

 // 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.
 
 #ifndef CHROME_BROWSER_EXTENSIONS_EXTENSION_APITEST_H_
 #define CHROME_BROWSER_EXTENSIONS_EXTENSION_APITEST_H_
 
 #include <deque>
 #include <string>
 
@@ skipping 130 matching lines @@
   bool RunExtensionSubtest(const char* extension_name,
                            const std::string& page_url,
                            int flags);
 
   // Load |page_url| and wait for pass / fail notification from the extension
   // API on the page.
   bool RunPageTest(const std::string& page_url);
   bool RunPageTest(const std::string& page_url, int flags);
 
   // Similar to RunExtensionTest, except used for running tests in platform app
-  // shell windows.
+  // shell windows. After running the test will close all shell windows and wait
+  // for the background page to be unloaded.
   bool RunPlatformAppTest(const char* extension_name);
 
+  // Similar to RunPlatformAppTest, except after running the test returns
+  // without closing shell windows or waiting for the background page to be
+  // unloaded.
+  bool RunPlatformAppTestReturnImmediately(const char* extension_name);
+
   // Start the test server, and store details of its state.  Those details
   // will be available to javascript tests using chrome.test.getConfig().
   bool StartTestServer();
 
   // Start the test WebSocket server, and store details of its state. Those
   // details will be available to javascript tests using
   // chrome.test.getConfig().
   bool StartWebSocketServer(const FilePath& root_directory);
 
   // Test that exactly one extension loaded.  If so, return a pointer to
@@ skipping 13 matching lines @@
 
   // Hold details of the test, set in C++, which can be accessed by
   // javascript using chrome.test.getConfig().
   scoped_ptr<DictionaryValue> test_config_;
 
   // Hold the test WebSocket server.
   scoped_ptr<net::TestServer> websocket_server_;
 };
 
 #endif  // CHROME_BROWSER_EXTENSIONS_EXTENSION_APITEST_H_