Add missing Security histograms to histograms.xml

This adds three missing histograms to histograms.xml that should have
been introduced in https://crrev.com/c/914468: two enums,
Security.SecurityLevel.OnCommit and Security.SecurityLevel.OnComplete,
and one suffixed histogram, Security.TimeOnPage.

Bug: 803540
Change-Id: I608604067c422703efa130dbc16f271529d0bbf6
Reviewed-on: https://chromium-review.googlesource.com/949608
Commit-Queue: Christopher Thompson <cthomp@chromium.org>
Reviewed-by: Mark Pearson <mpearson@chromium.org>
Cr-Commit-Position: refs/heads/master@{#540945}
1 file changed