Fixed check return warnings from Coverity.

chrome/browser/policy/policy_loader_win.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 "chrome/browser/policy/policy_loader_win.h"
 
 #include <string>
 
 #include <string.h>
 
@@ skipping 70 matching lines @@
     { kRegistryRecommendedSubKey, POLICY_LEVEL_RECOMMENDED  },
   };
 
   // Lookup at the mandatory path for both user and machine policies first, and
   // then at the recommended path.
   for (size_t k = 0; k < arraysize(kKeyPaths); ++k) {
     for (size_t h = 0; h < arraysize(kHives); ++h) {
       string16 path(kKeyPaths[k].path);
       if (!key_path.empty())
         path += kPathSep + key_path;
-      key->Open(kHives[h].hive, path.c_str(), KEY_READ);
+      LONG rc = key->Open(kHives[h].hive, path.c_str(), KEY_READ);
+      DCHECK_EQ(rc, ERROR_SUCCESS);

[Mattias Nissler (ping if slow), 2012/07/26 09:37:06]

I think this is also wrong. Keys may not exist, so it's perfectly fine for this
to fail (and we shouldn't DCHECK). That's why we have the key->Valid() check
below.

[Joao da Silva, 2012/07/26 10:04:33]

Yep. Rewrite as:

if (key->Open(...) != ERROR_SUCCESS || !key->Valid())
  continue;

[Danh Nguyen, 2012/07/26 15:46:27]

Fixed per Joao's advice.  Thanks.

       if (!key->Valid())
         continue;
       if (value_name.empty() || key->HasValue(value_name.c_str())) {
         *level = kKeyPaths[k].level;
         *scope = kHives[h].scope;
         return true;
       }
     }
   }
   return false;
@@ skipping 578 matching lines @@
 
 void PolicyLoaderWin::OnObjectSignaled(HANDLE object) {
   DCHECK(object == user_policy_changed_event_.handle() ||
          object == machine_policy_changed_event_.handle())
       << "unexpected object signaled policy reload, obj = "
       << std::showbase << std::hex << object;
   Reload(false);
 }
 
 }  // namespace policy