There is no safe way to invoke this method correctly since the
package might not be installed for certain user type by OEM.
Thus, improve error handling and logging into WTF counter metrics.
Test: Manual:
1. Use internal main branch
2. Modify xml under vendor/google/data/etc/sysconfig to
configure tethering only installs on the SYSTEM user
3. Mock the device as entitlement required (ag/29664886)
4. Create a secondary user which has the permission to
enable tethering (go/hsum)
5. adb shell pm list packages --user 10 | grep tether
6. m statsd_testdrive && statsd_testdrive -e 979
7. Enable tethering
Test: atest TetheringTests:EntitlementManagerTest
Bug: 382628161
Change-Id: I233cad672e41d2b4687e53e61b93dcea9eb07817
a80fd3deba