Fix incorrect message being sent for all intents.

Only send the CHECK_PACKAGE_IDLE_STATE message for
ACTION_PACKAGE_CHANGED and not for ACTION_PACKAGE_ADDED.

Bug: 214580000
Test: atest UsageStatsDatabaseTest
Test: manually verify buckets are restored
Change-Id: Iac1433b9b7e3904eb7f753cd0617ac64ab6f7944