Restrict activity launch when caller is running in the background

Test: test on device + atest-src BackgroundActivityLaunchTest#testBackgroundActivityBlockedInStartNextMatchingActivity
Bug: 230492947
(cherry picked from https://googleplex-android-review.googlesource.com/q/commit:d54a64bdf71d1c91542b6885149fd176622ad0b4)
Merged-In: I1a0c13e74622d301866efaca1b5351a6b241ebe5
Change-Id: I1a0c13e74622d301866efaca1b5351a6b241ebe5