[iOS][MF] Adds password related histograms

Bug: 878388
Change-Id: Ia0a6622596753d87888e480401e38f7ef61ae539
Reviewed-on: https://chromium-review.googlesource.com/c/1326013
Reviewed-by: Robert Kaplow <rkaplow@chromium.org>
Commit-Queue: Javier Ernesto Flores Robles <javierrobles@chromium.org>
Cr-Commit-Position: refs/heads/master@{#606890}
2 files changed