[DO NOT MERGE] Update kernel timezone if call to setTime causes DST offset to change

If AlarmManager#setTime is called with a time that has a different DST
offset than the current system time, update the kernel timezone offset
with the correct value for the time being set.

Test: Manually set time to two times with different DST offsets, ensure
kernel time zone updates properly.

Bug: 80142036
Bug: 80098370
Change-Id: I8884bce471cf4b95372d6d33a36e8c9e92bd6a96
(cherry picked from commit f5d585aec9)

services/core/java/com/android/server/AlarmManagerService.java

@@ -1388,7 +1388,19 @@ class AlarmManagerService extends SystemService {
         }
 
         synchronized (mLock) {
-            return setKernelTime(mNativeData, millis) == 0;
+            final long currentTimeMillis = System.currentTimeMillis();
+            setKernelTime(mNativeData, millis);
+            final TimeZone timeZone = TimeZone.getDefault();
+            final int currentTzOffset = timeZone.getOffset(currentTimeMillis);
+            final int newTzOffset = timeZone.getOffset(millis);
+            if (currentTzOffset != newTzOffset) {
+                Slog.i(TAG, "Timezone offset has changed, updating kernel timezone");
+                setKernelTimezone(mNativeData, -(newTzOffset / 60000));
+            }
+            // The native implementation of setKernelTime can return -1 even when the kernel
+            // time was set correctly, so assume setting kernel time was successful and always
+            // return true.
+            return true;
         }
     }