Fix UBSan errors (left shift of negative value)

webrtc/modules/audio_coding/codecs/ilbc/enhancer_interface.c

 /*
  *  Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 134 matching lines @@
     /* Calculate normalized corr^2 and ener */
     for (i=0;i<3;i++) {
       corrSh = 15-WebRtcSpl_GetSizeInBits(corrmax[i]);
       ener = WebRtcSpl_DotProductWithScale(regressor - lagmax[i],
                                            regressor - lagmax[i],
                                            ENH_BLOCKL_HALF, shifts);
       enerSh = 15-WebRtcSpl_GetSizeInBits(ener);
       corr16[i] = (int16_t)WEBRTC_SPL_SHIFT_W32(corrmax[i], corrSh);
       corr16[i] = (int16_t)((corr16[i] * corr16[i]) >> 16);
       en16[i] = (int16_t)WEBRTC_SPL_SHIFT_W32(ener, enerSh);
-      totsh[i] = enerSh - (corrSh << 1);
+      totsh[i] = enerSh - 2 * corrSh;
     }
 
     /* Compare lagmax[0..3] for the (corr^2)/ener criteria */
     ind = 0;
     for (i=1; i<3; i++) {
       if (totsh[ind] > totsh[i]) {
         sh = WEBRTC_SPL_MIN(31, totsh[ind]-totsh[i]);
         if (corr16[ind] * en16[i] < (corr16[i] * en16[ind]) >> sh) {
           ind = i;
         }
@@ skipping 202 matching lines @@
     WebRtcIlbcfix_Enhancer(out + iblock * ENH_BLOCKL,
                            enh_buf,
                            ENH_BUFL,
                            iblock * ENH_BLOCKL + startPos,
                            enh_period,
                            WebRtcIlbcfix_kEnhPlocs, ENH_NBLOCKS_TOT);
   }
 
   return (lag);
 }