DevTools: Add user metrics for saving a file to workspace

Chromium counterpart: https://codereview.chromium.org/423713008/

R=pfeldman
BUG=399449
NOTRY=TRUE

Review URL: https://codereview.chromium.org/439463002

git-svn-id: svn://svn.chromium.org/blink/trunk@179444 bbb929c8-8fbe-4397-9dbb-9b2b20218538
spelling-should-replace-second-word.html: update expected output.

http://codereview.chromium.org/424183004 changed the test runnner's
spell check client to post an spellcheck event with a different
casing -- FinishSpellCheckEvent (was: finishSpellCheckEvent.) Update
expected test output accordingly.

TBR=jochen@chromium.org,yosin@chromium.org
BUG=399847
NOTRY=true

Review URL: https://codereview.chromium.org/437563003

git-svn-id: svn://svn.chromium.org/blink/trunk@179445 bbb929c8-8fbe-4397-9dbb-9b2b20218538