ChromeDriver: Convert mouse events into touch events

This patch uses Input.dispatchTouchEvent instead of
Emulation.setEmitTouchEventsForMouse. This gives more predictable
behavior and allows for each touch event to be awaited.

Bug: chromedriver:2144
Change-Id: Ic243c216e2f832844a64f8f2af894eb6cc4234d1
Reviewed-on: https://chromium-review.googlesource.com/1182506
Commit-Queue: Joel Einbinder <einbinder@chromium.org>
Reviewed-by: John Chen <johnchen@chromium.org>
Reviewed-by: Dmitry Gozman <dgozman@chromium.org>
Cr-Commit-Position: refs/heads/master@{#584904}
4 files changed