Reland "[Android MR] Postpone route selection until session launch"

This reverts commit 74e258c6b0861b76fb8a60b6149f30dd50947648.

Reason for revert: The previous revert was wrong.
This is still a necessary change

Original change's description:
> Revert "[Android MR] Postpone route selection until session launch"
> 
> This reverts commit 7c453583f0c622cf928bb5d628ae9def8f03279f.
> 
> Reason for revert: This introduces some regression in some cases. The old logic works just fine so it is safe to revert.
> 
> Original change's description:
> > [Android MR] Postpone route selection until session launch
> > 
> > Previously, we unselect and re-select the route due to CAF limitation.
> > The reason is that we need to set the receiver app ID after the user
> > choose a device. However CAF won't be able to know a device was selected
> > after the receiver app ID gets changed.
> > 
> > In this CL, to solve the issue, we intercept the click event in
> > MediaRouteChooserDialog (which would select the route automatically).
> > The route selection is postponed right before session launch. Therefore
> > we are able to set the receiver app ID and select the route to get rid
> > of CAF limitation.
> > 
> > Bug: 711860
> > Change-Id: I5b1534d36d540b62199a6fb739c56ad5131c2711
> > Reviewed-on: https://chromium-review.googlesource.com/c/1351893
> > Reviewed-by: Thomas Guilbert <tguilbert@chromium.org>
> > Commit-Queue: Zhiqiang Zhang <zqzhang@chromium.org>
> > Cr-Commit-Position: refs/heads/master@{#611437}
> 
> TBR=zqzhang@chromium.org,tguilbert@chromium.org
> 
> Change-Id: I30322daecf8c866fdda9e846d0cb37d9a319f033
> No-Presubmit: true
> No-Tree-Checks: true
> No-Try: true
> Bug: 711860
> Reviewed-on: https://chromium-review.googlesource.com/c/1352973
> Reviewed-by: Zhiqiang Zhang <zqzhang@chromium.org>
> Commit-Queue: Zhiqiang Zhang <zqzhang@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#611572}

TBR=zqzhang@chromium.org,tguilbert@chromium.org

# Not skipping CQ checks because original CL landed > 1 day ago.

Bug: 711860
Change-Id: I8bbeeb9e6917e07163bb0fbfacd1fa1c3f762a49
Reviewed-on: https://chromium-review.googlesource.com/c/1359822
Reviewed-by: Zhiqiang Zhang <zqzhang@chromium.org>
Commit-Queue: Zhiqiang Zhang <zqzhang@chromium.org>
Cr-Commit-Position: refs/heads/master@{#613403}
4 files changed