GitLab

Currently the intents to be handled in the foreground instance of
CustomTabActivity are delivered via a static reference in
BrowserSessionContentUtils, instead of delivering the intent via
ordinary Android mechanisms. This means, in particular, that intent
flags are lost in the process.

This poses a problem for "Single activity" TWA apps, specifically for
their ability to forward new incoming View intents to the running TWA.
We'd like this forwarding to be possible, and to work "out of the box"
with LauncherActivity.

Currently it works as follows. LauncherActivity starts a TWA, and keeps
running in background - this allows to customize it so that it would
continue communicating with TWA via CustomTabConnection. If a new
View intent comes in, it starts a new instance of LauncherActivity,
which in turn creates ChromeLauncherActivity, so the stack is:

LauncherActivity | CTA | LauncherActivity | ChromeLauncherActivity

ChromeLauncherActivity calls CTA via a static method, and kills itself,
which leaves the second LauncherActivity running. Setting SINGLE_TOP and
CLEAR_TOP intent flags on the client won't help, because these flags won't
reach CTA.

In this CL I make ChromeLauncherActivity launch CTA with SINGLE_TOP and
CLEAR_TOP if there is a foreground CTA with matching session. Otherwise,
the intent handling is kept the way it was, with all the logic untouched.

The fallback solution, in the case this one won't work out, is to just
call  finish() in LauncherActivity once it has launched a TWA. This would
mean it won't be able to both do the intent routing and keep communicating
via CustomTabConnection (and probably no client implementation would be
able to), which isn't good, but might not be a blocker for MVP release.

Companion CL: http://crrev.com/c/1349363

Bug: 907796
Change-Id: I8a2396b325baae2974d6b0dfb73c2ed2fb0519eb
Reviewed-on: https://chromium-review.googlesource.com/c/1349653
Commit-Queue: Pavel Shmakov <pshmakov@chromium.org>
Reviewed-by: Yusuf Ozuysal <yusufo@chromium.org>
Reviewed-by: Peter Conn <peconn@chromium.org>
Cr-Commit-Position: refs/heads/master@{#611375}