Fix typo in devtools js comment: closed shadow -> user agent shadow
Fix typo in devtools js comment: closed shadow -> user agent shadow

TBR=caseq, hayato
NOTRY=true

Review URL: https://codereview.chromium.org/1220313003

git-svn-id: bf5cd6ccde378db821296732a091cfbcf5285fbd@198314 bbb929c8-8fbe-4397-9dbb-9b2b20218538

Pluto-tv/blink-crosswalk,Pluto-tv/blink-crosswalk,Pluto-tv/blink-crosswalk,Pluto-tv/blink-crosswalk,Pluto-tv/blink-crosswalk,Pluto-tv/blink-crosswalk,Pluto-tv/blink-crosswalk,Pluto-tv/blink-crosswalk,Pluto-tv/blink-crosswalk,Pluto-tv/blink-crosswalk