Further improvements when app forges package info for autofill:

- Dont create a session if the component is not owned by the calling UID.
- Log metrics for forged attempts.
- Avoid possible NPEs on AutofillManager when context or client is null.

Test: cts-tradefed run commandAndExit cts-dev -m CtsAutoFillServiceTestCases -t android.autofillservice.cts.VirtualContainerActivityTest#testAppCannotFakePackageName
Test: cts-tradefed run commandAndExit cts-dev -m CtsAutoFillServiceTestCases

Bug: 69981710

Change-Id: I9695bc046f3eb8aeecfe44f80fd0366f68b2c635