Revert "A unified data class to represent all the InputConnection call"

This reverts commit 2757c248 [1].

Reason for revert:
We will try another approach to implement InputConnection task
cancellation without InputConnectionCommand.

 [1]: I86eba7185b4b0664c1b0b3da794dfc5eeddc725c

Bug: 194151409
Change-Id: I0ef1e1b498b77caf7704742d88c7c81944d75c42
Test: atest CtsInputMethodTestCases:InputConnectionEndToEndTest