Coverity: Fixing pass by value.
CID=101462, 101458, 101437, 101471, 101467

BUG=NONE
TEST=NONE

Review URL: http://codereview.chromium.org/9006023

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@115257 0039d316-1c4b-4281-b951-d872f2087c98
void ExtensionHelper::DidCreateDocumentElement(WebFrame* frame) {
  extension_dispatcher_->user_script_slave()->InjectScripts(
      frame, UserScript::DOCUMENT_START);
}

void ExtensionHelper::DidCreateDocumentElement(WebFrame* frame) {
  extension_dispatcher_->user_script_slave()->InjectScripts(
      frame, UserScript::DOCUMENT_START);
}
