Split TextClassifierEvent into multiple subclasses

As per the suggestion from API council, we now have a subclass for event
of each category.

Bug: 129344540

Test: atest frameworks/base/core/tests/coretests/src/android/view/textclassifier/
Test: atest cts/tests/tests/view/src/android/view/textclassifier/cts/
Test: atest frameworks/base/packages/ExtServices/tests/src/android/ext/services/notification/SmartActionsHelperTest.java

Change-Id: Ic43b33c2176447c40e64bd0e410e906d5fb9c4cc
7 files changed