[App Management] Refactor permission-view-header to a new element

This CL extracts permission view header from chrome app permission view and pwa permission view to avoid duplicate code.

Bug: 906508
Change-Id: If4335bf7fcf70ec2b5d429f1b632c66839ec6853
Reviewed-on: https://chromium-review.googlesource.com/c/1393127
Reviewed-by: calamity <calamity@chromium.org>
Commit-Queue: Cecilia Ni <ceciliani@google.com>
Cr-Commit-Position: refs/heads/master@{#619891}
9 files changed