[App Management] Add show_in_management field to App Service App struct.

This CL adds a show_in_management field to the App Service App struct,
which is used by the PageHandler to determine whether or not an app
should be displayed in the App Management page. This provides a way to
stop built-in Chrome apps and component extensions from showing up in
the page.

Bug: 906508
Change-Id: Ide70b56cd669ba62a5f7294c5fd8e30db11548f1
Reviewed-on: https://chromium-review.googlesource.com/c/1460208
Reviewed-by: Sam McNally <sammc@chromium.org>
Reviewed-by: Nigel Tao <nigeltao@chromium.org>
Reviewed-by: calamity <calamity@chromium.org>
Reviewed-by: Eric Willigers <ericwilligers@chromium.org>
Commit-Queue: Reka Norman <rekanorman@google.com>
Cr-Commit-Position: refs/heads/master@{#631554}
10 files changed