Revert "Disable Pre-reboot Dexopt."

This reverts commit 3efe8ed.

Reason for revert: Problem fixed

Bug: 356858364
Change-Id: I8e976a4e3f8120d672861b967a7765d23d1099a1

Author: jiakaiz-g

cmds/installd/otapreopt_script.sh

@@ -50,6 +50,37 @@ else
   exit 1
 fi
 
+# A source that infinitely emits arbitrary lines.
+# When connected to STDIN of another process, this source keeps STDIN open until
+# the consumer process closes STDIN or this script dies.
+function infinite_source {
+  while echo .; do
+    sleep 1
+  done
+}
+
+PR_DEXOPT_JOB_VERSION="$(pm art pr-dexopt-job --version)"
+if (( $? == 0 )) && (( $PR_DEXOPT_JOB_VERSION >= 3 )); then
+  # Delegate to Pre-reboot Dexopt, a feature of ART Service.
+  # ART Service decides what to do with this request:
+  # - If Pre-reboot Dexopt is disabled or unsupported, the command returns
+  #   non-zero. This is always the case if the current system is Android 14 or
+  #   earlier.
+  # - If Pre-reboot Dexopt is enabled in synchronous mode, the command blocks
+  #   until Pre-reboot Dexopt finishes, and returns zero no matter it succeeds or
+  #   not. This is the default behavior if the current system is Android 15.
+  # - If Pre-reboot Dexopt is enabled in asynchronous mode, the command schedules
+  #   an asynchronous job and returns 0 immediately. The job will then run by the
+  #   job scheduler when the device is idle and charging.
+  if infinite_source | pm art on-ota-staged --slot "$TARGET_SLOT_SUFFIX"; then
+    # Handled by Pre-reboot Dexopt.
+    exit 0
+  fi
+  echo "Pre-reboot Dexopt not enabled. Fall back to otapreopt."
+else
+  echo "Pre-reboot Dexopt is too old. Fall back to otapreopt."
+fi
+
 if [ "$(/system/bin/otapreopt_chroot --version)" != 2 ]; then
   # We require an updated chroot wrapper that reads dexopt commands from stdin.
   # Even if we kept compat with the old binary, the OTA preopt wouldn't work due