Set a "metrics_client_id" crash key instead of "guid" on Mac OS X

chrome/app/chrome_crash_reporter_client.h

 // Copyright 2013 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_APP_CHROME_CRASH_REPORTER_CLIENT_H_
 #define CHROME_APP_CHROME_CRASH_REPORTER_CLIENT_H_
 
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "components/crash/app/crash_reporter_client.h"
 
 namespace chrome {
 
 class ChromeCrashReporterClient : public crash_reporter::CrashReporterClient {
  public:
   ChromeCrashReporterClient();
   ~ChromeCrashReporterClient() override;
 
   // crash_reporter::CrashReporterClient implementation.
+#if !defined(OS_MACOSX)
   void SetCrashReporterClientIdFromGUID(
       const std::string& client_guid) override;
+#endif
 #if defined(OS_WIN)
   virtual bool GetAlternativeCrashDumpLocation(base::FilePath* crash_dir)
       override;
   virtual void GetProductNameAndVersion(const base::FilePath& exe_path,
                                         base::string16* product_name,
                                         base::string16* version,
                                         base::string16* special_build,
                                         base::string16* channel_name) override;
   virtual bool ShouldShowRestartDialog(base::string16* title,
                                        base::string16* message,
@@ skipping 31 matching lines @@
 
   bool EnableBreakpadForProcess(const std::string& process_type) override;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(ChromeCrashReporterClient);
 };
 
 }  // namespace chrome
 
 #endif  // CHROME_APP_CHROME_CRASH_REPORTER_CLIENT_H_