Usage of PendingIntent.FLAG_IMMUTABLE

[mbiebl]

Since bf18d02 the code unconditionally uses PendingIntent.FLAG_IMMUTABLE

According to https://developer.android.com/reference/android/app/PendingIntent#FLAG_IMMUTABLE though, this flag was only introduced in API level 23.
As davx5 still supports API level 21 (according to app/build.gradle), should the usage of this flag be guarded by a version check?
Similar to what's already done in https://github.com/bitfireAT/davx5-ose/blob/dev-ose/app/src/main/java/at/bitfire/davdroid/syncadapter/SyncUtils.kt#L53

[rfc2822]

As far as I remember, Android 23 forces FLAG_IMMUTABLE to be set, otherwise showing the notification crashes.

Earlier Android versions don't seem to have a problem with the flag set… so I'd rather remove the if condition from SyncUtils L53.

[mbiebl]

Do older Android versions simply ignore the flag?
I.e. are you sure it's safe to specify it undonditionally?

[rfc2822]

It seems so because with the current code there was never a single indication of any problem on older Android devices.

[mbiebl]

ok, thanks