Made code in DocumentMarkerController.cpp conform to blink's coding 
guidelines and improved performance in WebViewImpl.cpp a bit.

Review URL: https://codereview.chromium.org/479803002

git-svn-id: svn://svn.chromium.org/blink/trunk@180447 bbb929c8-8fbe-4397-9dbb-9b2b20218538