DevTools: Use Ctrl-Tilde instead of Cmd-Tilde for show console shortcut on mac.

BUG=330265

Review URL: https://codereview.chromium.org/116573012

git-svn-id: svn://svn.chromium.org/blink/trunk@164294 bbb929c8-8fbe-4397-9dbb-9b2b20218538