Support custom user strings.

Use UserHandle.parseUserArg() when parsing adb command flags to enable
parsing "cur" and other special user strings.

Bug: 282063891
Test: atest CtsJobSchedulerTestCases
Test: `adb shell cmd jobscheduler run --user cur com.android.settings 2131427352`
Change-Id: Ibe06f536f1de760a5604d067b6c1894f756a17c6

apex/jobscheduler/service/java/com/android/server/job/JobSchedulerShellCommand.java

@@ -180,7 +180,7 @@ public final class JobSchedulerShellCommand extends BasicShellCommandHandler {
 
                 case "-u":
                 case "--user":
-                    userId = Integer.parseInt(getNextArgRequired());
+                    userId = UserHandle.parseUserArg(getNextArgRequired());
                     break;
 
                 case "-n":
@@ -199,6 +199,10 @@ public final class JobSchedulerShellCommand extends BasicShellCommandHandler {
             return -1;
         }
 
+        if (userId == UserHandle.USER_CURRENT) {
+            userId = ActivityManager.getCurrentUser();
+        }
+
         final String pkgName = getNextArgRequired();
         final int jobId = Integer.parseInt(getNextArgRequired());