GestureConverter: remove checks on choreographer flag

The only reason it needed to check the flag was when calling
mPointerController->getPosition, but since change
I475f3286c83b90e161e186e62c2842e539434603 that method handles the check
itself.

Bug: 245989146
Test: manual tests of movement and gestures with an Apple Magic Trackpad
Test: atest inputflinger_tests:GestureConverterTest \
            inputflinger_tests:GestureConverterTestWithChoreographer
Change-Id: I2ba46ba863ba8cd3a6caa94ec0dfafa7273df97b