Fixed the following warnings:

CID=104268,104216,104131,104058


Review URL: https://chromiumcodereview.appspot.com/10830022

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@148638 0039d316-1c4b-4281-b951-d872f2087c98

chrome/browser/policy/managed_mode_policy_provider.cc

@@ -43,6 +43,8 @@ const base::Value* ManagedModePolicyProvider::GetPolicy(
     const std::string& key) const {
   base::DictionaryValue* dict = GetCachedPolicy();
   base::Value* value = NULL;
+
+  // Returns NULL if the key doesn't exist.
   dict->GetWithoutPathExpansion(key, &value);
   return value;
 }

chrome/browser/policy/policy_loader_win.cc

@@ -88,9 +88,10 @@ bool LoadHighestPriorityKey(const string16& key_path,
       string16 path(kKeyPaths[k].path);
       if (!key_path.empty())
         path += kPathSep + key_path;
-      key->Open(kHives[h].hive, path.c_str(), KEY_READ);
-      if (!key->Valid())
+      if (key->Open(kHives[h].hive, path.c_str(), KEY_READ) != ERROR_SUCCESS ||
+          !key->Valid()) {
         continue;
+      }
       if (value_name.empty() || key->HasValue(value_name.c_str())) {
         *level = kKeyPaths[k].level;
         *scope = kHives[h].scope;

chrome/browser/value_store/testing_value_store.cc

@@ -98,8 +98,8 @@ ValueStore::WriteResult TestingValueStore::Set(
   scoped_ptr<ValueStoreChangeList> changes(new ValueStoreChangeList());
   for (DictionaryValue::Iterator it(settings); it.HasNext(); it.Advance()) {
     Value* old_value = NULL;
-    storage_.GetWithoutPathExpansion(it.key(), &old_value);
-    if (!old_value || !old_value->Equals(&it.value())) {
+    if (!storage_.GetWithoutPathExpansion(it.key(), &old_value) ||
+        !old_value->Equals(&it.value())) {
       changes->push_back(
           ValueStoreChange(
               it.key(),