GitLab

Refactoring of the internal input events blocker in
TabletModeController.

The input events should only be blocked if 1) we're currently in tablet
mode or 2) we're currently in clamshell mode but the lid is flipped over,
i.e., we are in laptop mode because of an attached external mouse.

Bug: b/118049922, 887042
Test: Newly added test and existing tests passed.
      Also manually tested on convertible/clamshell/tablet devices

Change-Id: I93d963cfab2ae14bd1cad19675f0ed4fed88c1b0
Reviewed-on: https://chromium-review.googlesource.com/c/1297577Reviewed-by: Xiyuan Xia <xiyuan@chromium.org>
Commit-Queue: Xiaoqian Dai <xdai@chromium.org>
Cr-Commit-Position: refs/heads/master@{#602370}