[Opus] Update to v1.2.1

third_party/opus/src/silk/decode_frame.c

 /***********************************************************************
 Copyright (c) 2006-2011, Skype Limited. All rights reserved.
 Redistribution and use in source and binary forms, with or without
 modification, are permitted provided that the following conditions
 are met:
 - Redistributions of source code must retain the above copyright notice,
 this list of conditions and the following disclaimer.
 - Redistributions in binary form must reproduce the above copyright
 notice, this list of conditions and the following disclaimer in the
 documentation and/or other materials provided with the distribution.
@@ skipping 79 matching lines @@
         silk_PLC( psDec, psDecCtrl, pOut, 0, arch );
 
         psDec->lossCnt = 0;
         psDec->prevSignalType = psDec->indices.signalType;
         silk_assert( psDec->prevSignalType >= 0 && psDec->prevSignalType <= 2 );
 
         /* A frame has been decoded without errors */
         psDec->first_frame_after_reset = 0;
     } else {
         /* Handle packet loss by extrapolation */
+        psDec->indices.signalType = psDec->prevSignalType;
         silk_PLC( psDec, psDecCtrl, pOut, 1, arch );
     }
 
     /*************************/
     /* Update output buffer. */
     /*************************/
     silk_assert( psDec->ltp_mem_length >= psDec->frame_length );
     mv_len = psDec->ltp_mem_length - psDec->frame_length;
     silk_memmove( psDec->outBuf, &psDec->outBuf[ psDec->frame_length ], mv_len * sizeof(opus_int16) );
     silk_memcpy( &psDec->outBuf[ mv_len ], pOut, psDec->frame_length * sizeof( opus_int16 ) );
@@ skipping 10 matching lines @@
 
     /* Update some decoder state variables */
     psDec->lagPrev = psDecCtrl->pitchL[ psDec->nb_subfr - 1 ];
 
     /* Set output frame length */
     *pN = L;
 
     RESTORE_STACK;
     return ret;
 }