M0277 FIX_PCM_DISABLEFILTER broken

[bheng]

1.) The following code to skip over PCM pixels fails to move the destination pixel pointer pRec before continuing to the next block. Therefore, the destination pointer will be misaligned with the source and the rest of the row will be corrupted.

    if( isPCMFilterDisabled && cl.classIdx == AdaptiveLoopFilter::m_ALF_UNUSED_CLASSIDX && transposeIdx == AdaptiveLoopFilter::m_ALF_UNUSED_TRANSPOSIDX )
    {
        continue;
    }

2.) The code below used to determine if a chroma CU is PCM uses the wrong locations. The locations (i,j) are chroma pixel locations. The code below treats them as if they were luma pixel locations instead. So the CU lookup will be wrong.

    Position pos(i, j);
    CodingUnit* cu = isDualTree ? cs.getCU(recalcPosition(nChromaFormat, CH_L, CH_C, pos), CH_C) : cs.getCU(pos, CH_L);

[bheng]

One potential fix can be found here:
​https://vcgit.hhi.fraunhofer.de/jvet/VVCSoftware_VTM/merge_requests/346

[ksuehring]

The fix was merged.