Limit alt+click -> right-click remapping to touchpads only

Many media and creative suite applications make use of
Alt+Click actions, but we always rewrite it to Right-Click
without giving the users a way to turn this behavior off.
Users of such applications often use external mice, which
already have an independent right click button.

This CL limits this behavior to events coming from touchpad
devices.

BUG=890648
TEST=Expanded tests.

Change-Id: I1b72eb4d9986e9139d7c6193cc2f808a6d9cad06
Reviewed-on: https://chromium-review.googlesource.com/c/1255605
Reviewed-by: Sadrul Chowdhury <[email protected]>
Reviewed-by: Steven Bennetts <[email protected]>
Commit-Queue: Ahmed Fakhry <[email protected]>
Cr-Commit-Position: refs/heads/master@{#599783}
3 files changed