Add a do_not_sync pref to ExtensionPrefs.

chrome/browser/extensions/crx_installer.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_CRX_INSTALLER_H_
 #define CHROME_BROWSER_EXTENSIONS_CRX_INSTALLER_H_
 
 #include <string>
+#include <vector>
 
 #include "base/compiler_specific.h"
 #include "base/files/file_path.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/weak_ptr.h"
 #include "base/version.h"
 #include "chrome/browser/extensions/blacklist.h"
 #include "chrome/browser/extensions/extension_install_prompt.h"
 #include "chrome/browser/extensions/extension_installer.h"
 #include "chrome/browser/extensions/extension_service.h"
@@ skipping 170 matching lines @@
       install_flags_ &= ~kInstallFlagInstallImmediately;
   }
 
   void set_is_ephemeral(bool val) {
     if (val)
       install_flags_ |= kInstallFlagIsEphemeral;
     else
       install_flags_ &= ~kInstallFlagIsEphemeral;
   }
 
+  void set_install_flag(int flag, bool val) {
+    if (val)
+      install_flags_ |= flag;
+    else
+      install_flags_ &= ~flag;
+  }
+
   bool did_handle_successfully() const { return did_handle_successfully_; }
 
   Profile* profile() { return installer_.profile(); }
 
   const Extension* extension() { return installer_.extension().get(); }
 
  private:
   friend class ::ExtensionServiceTest;
   friend class ExtensionUpdaterTest;
   friend class ExtensionCrxInstallerTest;
@@ skipping 205 matching lines @@
 
   // Gives access to common methods and data of an extension installer.
   ExtensionInstaller installer_;
 
   DISALLOW_COPY_AND_ASSIGN(CrxInstaller);
 };
 
 }  // namespace extensions
 
 #endif  // CHROME_BROWSER_EXTENSIONS_CRX_INSTALLER_H_