Skip some unnecessary allocations

- Move new matrix/rect construction to if the param is set on the
  builder, we only apply the params if the flags are set anyways
  and if the caller doesn't set those params then we are allocating
  new objects unnecessarily
- Always recycle motion event

Bug: 183756396
Test: Take memory profile when dragging pip
Change-Id: Ie7457c8c508ee61bd27daeebe486c39a5cebe7d7