- Use 'tx_size' in function signatures.
- filter_intra_taps_3 and filter_intra_taps_4 updated to support
  TX_SIZES_ALL (thanks to yuec@)

With these changes, filter-intra works correctly with rect-intra-pred.
So, we remove the temporary workaround for this.

Change-Id: Ide0f593419c21a74c08c61859f8dad918ca169fa