Revert of CQ to always post a message when Commit box is unchecked. (https://codereview.chromium.org/138173005/)

Reason for revert:
This created a lot of spam at commit event for some obscure reason. I couldn't fix it fast, so reverting.

Original issue's description:
> Made _discard_pending() always post a message. Added meaningful
> default messages to all the places where it is called in the code.  In
> particular, CQ will now always post a message whenever the Commit
> checkbox is unchecked, for any reason.
> 
> Updated unit tests accordingly, and made them a bit more robust by
> adding an error message to the failing FakeVerifier.
> 
> This does NOT fix the bug, but will hopefully give more visibility to
> developers when a CL is dropped.
> 
> BUG=238283
> 
> Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=247488

TBR=phajdan.jr@chromium.org
NOTREECHECKS=true
NOTRY=true
BUG=238283

Review URL: https://codereview.chromium.org/138133014

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/commit-queue@248624 0039d316-1c4b-4281-b951-d872f2087c98
3 files changed