Fix build break in pyautolib with gcc >= 4.5.

chrome/test/pyautolib/pyautolib.cc

 // Copyright (c) 2011 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.
 
 #include "base/memory/scoped_ptr.h"
 #include "base/string_number_conversions.h"
 #include "base/string_util.h"
 #include "base/utf_string_conversions.h"
 #include "chrome/test/automation/extension_proxy.h"
 #include "chrome/test/automation/tab_proxy.h"
@@ skipping 226 matching lines @@
       wait_for_open);
   EXPECT_TRUE(completed);
   return completed;
 }
 
 std::string PyUITestBase::_GetBookmarksAsJSON() {
   scoped_refptr<BrowserProxy> browser_proxy =
       automation()->GetBrowserWindow(0);  // Window doesn't matter.
   EXPECT_TRUE(browser_proxy.get());
   if (!browser_proxy.get())
-    return false;
+    return NULL;

[Nirnimesh, 2011/05/04 18:45:39]

This should be changed to std::string("{}") to indicate a valid (but empty) json
string.

 
   std::string s;
   EXPECT_TRUE(browser_proxy->GetBookmarksAsJSON(&s));
   return s;
 }
 
 bool PyUITestBase::AddBookmarkGroup(std::wstring& parent_id, int index,
                                     std::wstring& title) {
   scoped_refptr<BrowserProxy> browser_proxy =
       automation()->GetBrowserWindow(0);  // Window doesn't matter.
@@ skipping 139 matching lines @@
   // TODO(phadjan.jr): figure out a way to unambiguously report error.
   if (!browser_proxy.get())
     return cookie_val;
   scoped_refptr<TabProxy> tab_proxy = browser_proxy->GetTab(tab_index);
   EXPECT_TRUE(tab_proxy.get());
   if (!tab_proxy.get())
     return cookie_val;
   EXPECT_TRUE(tab_proxy->GetCookies(cookie_url, &cookie_val));
   return cookie_val;
 }