GitLab

There are two input type enums:
* one in the autocomplete code
* one in the metrics code that's used for UMA logging;
  this one is meant to remain stable

As part of fixing the linked bug, I created
https://codereview.chromium.org/314773002/
whch needed an input type enum, one which would remain stable.
It didn't necessarily have to be the metrics enum.

After discussion with the UMA folks (who deal with how to handle
stable enum problems all the time), we reached the conclusion
that we should have one stable enum and use it everywhere.  That's
the cleanest answer.

This single enum has to live in the metrics directory because metrics
is a component.

This change combines the two existing enums into one, putting the
new enum in a new file in the metrics directory.  The reason for
a new file is so we can include it without include the whole
OmniboxEventProto or any other metrics code.

The main files to review are autocomplete_input.h and *.proto.
All other changes are a mechanical result of the changes in
those three files.

The internal proto change has been submitted.

TBR=stevenjb
for the trivial change to chrome/browser/ui/app_list/search/omnibox_provider.cc
that removes an unnecessary include

BUG=284781
NOTRY=True

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=275696

Review URL: https://codereview.chromium.org/319523005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@275713 0039d316-1c4b-4281-b951-d872f2087c98