GitLab

Now that the ScrollToExpandPaymentHandler/ExpandablePaymentHandler
feature has been enabled by default, this CL is to clean up the
switch of it.

Highlights in this CL:
* Removed the CCT payment handler support from ServiceTabLauncher. It
  seems reasonable to combine the two branches, but I will leave it
  to follow-up CLs.
* Removed the code to disable the feature from
  payment_handler_exploit_browsertest.cc.
* Removed slide_out_down because CQ warns of unused resources.

Bug: 1157895
Change-Id: I76c96704388c52bdb3ae9c2d17f940cfa29c76b0
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2585809Reviewed-by: Matthew Jones <mdjones@chromium.org>
Reviewed-by: Michael Thiessen <mthiesse@chromium.org>
Reviewed-by: Rouslan Solomakhin <rouslan@chromium.org>
Commit-Queue: Liquan (Max) Gu <maxlg@chromium.org>
Cr-Commit-Position: refs/heads/master@{#836649}