Specify FLAG_IMMUTABLE when creating PendingIntent

Targeting S+ (version 31 and above) requires that one of
FLAG_IMMUTABLE or FLAG_MUTABLE be specified when creating a
PendingIntent. So this CL uses FLAG_IMMUTABLE to create
the PendingIntent because the flag is recommended in most cases.

Bug: 192103710
Test: manual
Change-Id: I2ab79dc4a0e6279676135a34ee8230190cbdd27e
1 file changed
tree: 07b9563d344b937da0cd4a98a1e6f3312df4e41a
  1. res/
  2. src/
  3. Android.bp
  4. AndroidManifest.xml
  5. OWNERS
  6. PREUPLOAD.cfg