Make MyPackageMonitor#onPackageDataCleared multi-user aware

This is a follow up CL to our previous CL [1], which aimed to fix Bug
267124364 but forgot to take care of multi-user scenarios (Bug 328098968).

With this commit

  InputMethodManagerService.MyPackageMonitor#onPackageDataCleared

becomes fully multi-user aware.

The corresponding CTS change [2] ensures that this scenario remains
fixed.

 [1]: I159d9b7a2d1dcc8df478bb45d0be706d615724a2
 [2]: Ie54f3674ca0a48cef090e528da9a414935cf74e6

Bug: 267124364
Fix: 328098968
Test: atest CtsInputMethodInstallTestCases:AdditionalSubtypeLifecycleTest
Change-Id: If42c518765171ff8cb51af000542671676cd3801