GitLab

Add 2 new UMAs for the files app:
- FileBrowser.SelectSearch, recorded when the user selects the 'Search' button
- FileBrowser.ToggleFileListType, recorded when the user switches between the
  'grid view' and 'list view' options of the files app

mouse), and change the grid view type, then check chrome://histograms.

Test: Select the search box (with keyboard shortcuts, or with tab, or with the
Bug: 397213
Cq-Include-Trybots: master.tryserver.chromium.linux:closure_compilation
Change-Id: Icf073dfae57717a91a6f6dbedc3c3d99dcecbdb3
Reviewed-on: https://chromium-review.googlesource.com/957566
Commit-Queue: Sasha Morrissey <sashab@chromium.org>
Reviewed-by: Ilya Sherman <isherman@chromium.org>
Reviewed-by: Naoki Fukino <fukino@chromium.org>
Cr-Commit-Position: refs/heads/master@{#546021}