Add in-profile external_extensions.json file for Chrome OS OEM customization.

chrome/common/chrome_paths.cc

 // Copyright (c) 2011 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/common/chrome_paths.h"
 
 #include "base/command_line.h"
 #include "base/file_util.h"
 #include "base/logging.h"
 #include "base/path_service.h"
@@ skipping 302 matching lines @@
       cur = cur.Append(FILE_PATH_LITERAL("Managed Preferences"));
       char* login = getlogin();
       if (!login)
         return false;
       cur = cur.AppendASCII(login);
       if (!file_util::PathExists(cur))  // we don't want to create this
         return false;
       break;
     }
 #endif
+#if defined(OS_CHROMEOS)
+    case chrome::DIR_USER_EXTERNAL_EXTENSIONS: {
+      if (!PathService::Get(chrome::DIR_USER_DATA, &cur))

[Erik does not do reviews, 2011/01/21 17:05:25]

I haven't been following your conversations with Dmitry here, but this seems a
bit odd.  How will the files get written separately into each user's profile? 
Won't it need to be in some shared location?

[Dmitry Polukhin, 2011/01/21 17:46:19]

It can't be some shared location because it needs to be writable by user. If it
is writable, it is security issue that one user will be able to install
extensions to all other user on this machine. There is solution with shared
location but it requires signing of the file itself so if file was unauthorized
we can detect it and don't apply. Moreover we already have such shared location
/opt/google/chrome/extensions/... Per-user location was chosen as a compromise
solution that is secure and is applied only once (i.e. if some app is installed
initially, it won't be removed with some OS update or server changes).

+        return false;
+      cur = cur.Append(FILE_PATH_LITERAL("External Extensions"));
+      break;
+    }
+#endif
     default:
       return false;
   }
 
   if (create_dir && !file_util::PathExists(cur) &&
       !file_util::CreateDirectory(cur))
     return false;
 
   *result = cur;
   return true;
 }
 
 // This cannot be done as a static initializer sadly since Visual Studio will
 // eliminate this object file if there is no direct entry point into it.
 void RegisterPathProvider() {
   PathService::RegisterProvider(PathProvider, PATH_START, PATH_END);
 }
 
 }  // namespace chrome