DevTools: Reset open resource dialog on navigation

BUG=364450
R=apavlov, lushnikov, pfeldman

Review URL: https://codereview.chromium.org/252473002

git-svn-id: svn://svn.chromium.org/blink/trunk@172479 bbb929c8-8fbe-4397-9dbb-9b2b20218538