Add a constant for low perceptible adj

NotificationListeners were moved to below FGS so
that they could be killed to relieve memory pressure.
Adding a proper place for it at oom adj 250.

Bug: 79848281
Test: Verify oom_adj value using dumpsys activity

Change-Id: I6059243b50921a696e967d88a7b21cbc6107856b
diff --git a/services/core/java/com/android/server/am/ProcessRecord.java b/services/core/java/com/android/server/am/ProcessRecord.java
index 5dccaf1..fcc857b 100644
--- a/services/core/java/com/android/server/am/ProcessRecord.java
+++ b/services/core/java/com/android/server/am/ProcessRecord.java
@@ -713,6 +713,8 @@
                 adj = ProcessList.VISIBLE_APP_ADJ;
             } else if (adj < ProcessList.PERCEPTIBLE_APP_ADJ) {
                 adj = ProcessList.PERCEPTIBLE_APP_ADJ;
+            } else if (adj < ProcessList.PERCEPTIBLE_LOW_APP_ADJ) {
+                adj = ProcessList.PERCEPTIBLE_LOW_APP_ADJ;
             } else if (adj < ProcessList.CACHED_APP_MIN_ADJ) {
                 adj = ProcessList.CACHED_APP_MIN_ADJ;
             } else if (adj < ProcessList.CACHED_APP_MAX_ADJ) {