Remove ".." from PathService take #2.

base/path_service.cc

 // 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.
 
 #include "base/path_service.h"
 
 #ifdef OS_WIN
 #include <windows.h>
 #include <shellapi.h>
 #include <shlobj.h>
@@ skipping 191 matching lines @@
   while (provider) {
     if (provider->func(key, &path))
       break;
     DCHECK(path.empty()) << "provider should not have modified path";
     provider = provider->next;
   }
 
   if (path.empty())
     return false;
 
+  if (path.ReferencesParent()) {
+    // Make sure path service never returns a path with ".." in it.
+    if (!file_util::AbsolutePath(&path)) {
+      return false;
+    }
+  }
   *result = path;
 
   base::AutoLock scoped_lock(path_data->lock);
   path_data->cache[key] = path;
 
   return true;
 }
 
 // static
 bool PathService::Override(int key, const FilePath& path) {
@@ skipping 82 matching lines @@
   while (iter) {
     DCHECK(key_start >= iter->key_end || key_end <= iter->key_start) <<
       "path provider collision";
     iter = iter->next;
   }
 #endif
 
   p->next = path_data->providers;
   path_data->providers = p;
 }