Move platform_thread to base/threading and put in the base namespace. I left ...

chrome/browser/renderer_host/resource_dispatcher_host_uitest.cc

 // Copyright (c) 2010 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 <sstream>
 #include <string>
 
 #include "base/command_line.h"
 #include "base/file_path.h"
 #include "base/path_service.h"
@@ skipping 198 matching lines @@
   ASSERT_TRUE(browser_proxy.get());
   scoped_refptr<TabProxy> tab(browser_proxy->GetActiveTab());
   ASSERT_TRUE(tab.get());
 
   // Cause the renderer to crash.
 #if defined(OS_WIN) || defined(USE_LINUX_BREAKPAD)
   expected_crashes_ = 1;
 #endif
   ASSERT_TRUE(tab->NavigateToURLAsync(GURL(chrome::kAboutCrashURL)));
   // Wait for browser to notice the renderer crash.
-  PlatformThread::Sleep(sleep_timeout_ms());
+  base::PlatformThread::Sleep(sleep_timeout_ms());
 
   // Navigate to a new cross-site page.  The browser should not wait around for
   // the old renderer's on{before}unload handlers to run.
   CheckTitleTest(L"content-sniffer-test0.html",
                  L"Content Sniffer Test 0", 1);
 }
 #endif  // !defined(OS_MACOSX)
 
 // Tests that cross-site navigations work when the new page does not go through
 // the BufferedEventHandler (e.g., non-http{s} URLs).  (Bug 1225872)
@@ skipping 96 matching lines @@
   GURL broken_url("chrome://theme");
   ASSERT_EQ(AUTOMATION_MSG_NAVIGATION_SUCCESS, tab->NavigateToURL(broken_url));
 
   // Make sure the navigation finishes.
   std::wstring tab_title;
   EXPECT_TRUE(tab->GetTabTitle(&tab_title));
   EXPECT_EQ(L"chrome://theme/ is not available", tab_title);
 }
 
 }  // namespace