Articulate the cancel behavior in the WebTouchEvent.

Articulate the cancel behavior in the WebTouchEvent.

Change the cancelable flag to be an enumeration so that we
can determine if it is blocking or non-blocking and the reason.

Wheel events will add this flag in a follow up CL.

BUG=601661
Review URL: https://codereview.chromium.org/1888163003

Cr-Commit-Position: refs/heads/master@{#388585}
(cherry picked from commit afb8f54b782055923cadd711452c2448f3f7b5b4)

Committed: https://chromium.googlesource.com/chromium/src/+/0d6939cf25aa552bc77692aabe894ba5ba0bd6de

[dtapuska, 2016-04-22 13:57:08]

Description was changed from

==========
Articulate the cancel behavior in the WebTouchEvent.

Change the cancelable flag to be an enumeration so that we
can determine if it is blocking or non-blocking and the reason.

Wheel events will add this flag in a follow up CL.

BUG=601661

Review URL: https://codereview.chromium.org/1888163003

Cr-Commit-Position: refs/heads/master@{#388585}
(cherry picked from commit afb8f54b782055923cadd711452c2448f3f7b5b4)
==========

to

==========
Articulate the cancel behavior in the WebTouchEvent.

Change the cancelable flag to be an enumeration so that we
can determine if it is blocking or non-blocking and the reason.

Wheel events will add this flag in a follow up CL.

BUG=601661

Review URL: https://codereview.chromium.org/1888163003

Cr-Commit-Position: refs/heads/master@{#388585}
(cherry picked from commit afb8f54b782055923cadd711452c2448f3f7b5b4)

Committed:
https://chromium.googlesource.com/chromium/src/+/0d6939cf25aa552bc77692aabe89...
==========

[dtapuska, 2016-04-22 13:57:10]

Committed patchset #1 (id:1) manually as
0d6939cf25aa552bc77692aabe894ba5ba0bd6de.