Ensure automatic battery saver won't stick

Fixes: 80527470
Test: Manual tests:
Test 1: (make sure automatic BS won't stick)
- Set up automatic battery saver at N%
- Wait until the battery goes below N% -> Battery saver will turn on
- Turn off the device
- Charge it until the battery goes above N%
- Turn on the device
- Make sure battery saver is off.

Test 1: (make sure manual BS will stick)
- Make sure the battery level is above the automatic threshold
- Manually enable BS
- Reboot
- Make sure battery saver is on.

Change-Id: I677fd586f6b25d0200392941cac2d13b57fe10b3

1 files changed, 7 insertions, 1 deletions

diff --git a/services/core/java/com/android/server/power/batterysaver/BatterySaverStateMachine.java b/services/core/java/com/android/server/power/batterysaver/BatterySaverStateMachine.java
index 06559df98351..dd6d71e3b7a3 100644
--- a/services/core/java/com/android/server/power/batterysaver/BatterySaverStateMachine.java
+++ b/services/core/java/com/android/server/power/batterysaver/BatterySaverStateMachine.java
@@ -141,8 +141,14 @@ public class BatterySaverStateMachine {
         if (DEBUG) {
             Slog.d(TAG, "onBootCompleted");
         }
-        // This is called with the power manager lock held. Don't do any
+        // Just booted. We don't want LOW_POWER_MODE to be persisted, so just always clear it.
+        putGlobalSetting(Global.LOW_POWER_MODE, 0);
+
+        // This is called with the power manager lock held. Don't do anything that may call to
+        // upper services. (e.g. don't call into AM directly)
+        // So use a BG thread.
         runOnBgThread(() -> {
+
             final ContentResolver cr = mContext.getContentResolver();
             cr.registerContentObserver(Settings.Global.getUriFor(
                     Settings.Global.LOW_POWER_MODE),