[Touchless] Don't show PWAs on the last tab button

We can detect if a site in Chrome history is from a PWA launched
through webapk by:
 * Constructing an intent with the URL of the site.
 * Using the queryIntentActivities method to check what intents
   launched the given URL.
 * Check if the intents that launched the URL have the webapk class
   name "org.chromium.webapk.shell_apk".

(cherry picked from commit 48877c8a1a8c7754ce664feaeed4bb6a349c0a06)

Bug: 968570
Change-Id: Ia3a51976f1876d3f21cddaf8c3ee34e34cee6f94
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1646138
Commit-Queue: Brandon Wylie <wylieb@chromium.org>
Reviewed-by: Pavel Yatsuk <pavely@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#666803}
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1652219
Reviewed-by: Brandon Wylie <wylieb@chromium.org>
Cr-Commit-Position: refs/branch-heads/3809@{#231}
Cr-Branched-From: d82dec1a818f378c464ba307ddd9c92133eac355-refs/heads/master@{#665002}

• chrome/android/touchless/java/src/org/chromium/chrome/browser/touchless/OpenLastTabMediator.java[diff]