Fix some coverity defects

CID=8235,14234,14014,14235,15391
BUG=none
TEST=trybots

Review URL: http://codereview.chromium.org/6676014

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@77781 0039d316-1c4b-4281-b951-d872f2087c98
diff --git a/content/browser/gpu_blacklist.cc b/content/browser/gpu_blacklist.cc
index 91301493..1724c5fe6 100644
--- a/content/browser/gpu_blacklist.cc
+++ b/content/browser/gpu_blacklist.cc
@@ -584,8 +584,7 @@
     return false;
 
   ListValue* list = NULL;
-  parsed_json.GetList("entries", &list);
-  if (list == NULL)
+  if (!parsed_json.GetList("entries", &list))
     return false;
 
   uint32 max_entry_id = 0;