Code: void PrintWebViewHelper::PrintNode(const WebKit::WebNode& node) {
  if (node.isNull() || !node.document().frame()) {
     return;
   }
 
   if (is_preview_enabled_) {
    print_preview_context_.InitWithNode(node);
    RequestPrintPreview(PRINT_PREVIEW_USER_INITIATED_CONTEXT_NODE);
  } else {
     WebKit::WebNode duplicate_node(node);
     Print(duplicate_node.document().frame(), duplicate_node);
   }
 }

Vulnerability Type: DoS 
CWE ID: CWE-399
Summary: Use-after-free vulnerability in Google Chrome before 23.0.1271.91 allows remote attackers to cause a denial of service or possibly have unspecified other impact via vectors related to printing.
Commit Message: Guard against the same PrintWebViewHelper being re-entered.

BUG=159165

Review URL: https://chromiumcodereview.appspot.com/11367076

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@165821 0039d316-1c4b-4281-b951-d872f2087c98