Support an --install-from-webstore command line switch

chrome/browser/extensions/startup_helper.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_STARTUP_HELPER_H_
 #define CHROME_BROWSER_EXTENSIONS_STARTUP_HELPER_H_
 
 #include "base/memory/ref_counted.h"
 #include "chrome/browser/extensions/pack_extension_job.h"
 
@@ skipping 15 matching lines @@
 
   // Handle --pack-extension flag from the |cmd_line| by packing the specified
   // extension. Returns false if the pack job failed.
   bool PackExtension(const CommandLine& cmd_line);
 
   // Handle --uninstall-extension flag from the |cmd_line| by uninstalling the
   // specified extension from |profile|. Returns false if the uninstall job
   // could not be started.
   bool UninstallExtension(const CommandLine& cmd_line, Profile* profile);
 
+  // Handle --install-from-webstore flag from |cmd_line| by downloading
+  // metadata from the webstore for the given id, prompting the user to
+  // confirm, and then downloading the crx and installing it.
+  bool InstallFromWebstore(const CommandLine& cmd_line, Profile* profile);
+
  private:
   scoped_refptr<PackExtensionJob> pack_job_;
   bool pack_job_succeeded_;
 
   DISALLOW_COPY_AND_ASSIGN(StartupHelper);
 };
 
 }  // namespace extensions
 
 #endif  // CHROME_BROWSER_EXTENSIONS_STARTUP_HELPER_H_