Add a new GetInstance() method for singleton classes used in chrome/browser files.

chrome/browser/memory_details_linux.cc

 // Copyright (c) 2006-2008 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 "chrome/browser/memory_details.h"
 
 #include <unistd.h>
 #include <fcntl.h>
 #include <dirent.h>
 
@@ skipping 216 matching lines @@
           }
         }
       }
 
       if (!found_parent)
         browsers_found.insert(i->pid);
     }
   }
 
   std::vector<pid_t> current_browser_processes;
-  const pid_t zygote = Singleton<ZygoteHost>()->pid();
+  const pid_t zygote = ZygoteHost::GetInstance()->pid();
   GetAllChildren(processes, getpid(), zygote, &current_browser_processes);
   ProcessData current_browser;
   GetProcessDataMemoryInformation(current_browser_processes, &current_browser);
   current_browser.name = chrome::kBrowserAppName;
   current_browser.process_name = L"chrome";
   process_data_.push_back(current_browser);
 
   // For each browser process, collect a list of its children and get the
   // memory usage of each.
   for (std::set<pid_t>::const_iterator
@@ skipping 14 matching lines @@
     }
 
     process_data_.push_back(browser);
   }
 
   // Finally return to the browser thread.
   BrowserThread::PostTask(
       BrowserThread::UI, FROM_HERE,
       NewRunnableMethod(this, &MemoryDetails::CollectChildInfoOnUIThread));
 }