Complete stylus force & tilt info plumbing in blink.

CromeOS now has low level support for stylus 3D orientation
data (tiltX/tiltY) and force. For example, a Wacom Intuos Pro
device with an Wacom Art Pen reports tiltX, tiltY & force
info when attached to a ChromeBook Pixel. This CL completes
the missing plumbing in blink so that the data is visible from JS.

BUG=516706

Review URL: https://codereview.chromium.org/1458643002

Cr-Commit-Position: refs/heads/master@{#360398}
5 files changed