GitLab

New interface (with default stub implementations) with the following:

  * Pass the event location rather than the underlying event (so that
    touch events or other data sources can be used instead of gesture events)
  * Method to query the handler whether it can handle a given event origin
    so we can avoid detecting (or blocking) margin events unnecessarily.
  * Adds a method for continuation/drag events.

Bug: internal b/78462154
Bug: internal b/78461207
Change-Id: I1bba715e98b6458bf079cacd71b4ef3403ae7260
Tested: manual test
Reviewed-on: https://chromium-review.googlesource.com/1028656
Commit-Queue: Ryan Daum <rdaum@chromium.org>
Reviewed-by: Sadrul Chowdhury <sadrul@chromium.org>
Reviewed-by: Alex Sakhartchouk <alexst@chromium.org>
Cr-Commit-Position: refs/heads/master@{#553767}