Merge changes I00c852e4,Ib31bf028

* changes:
  stagefright aacenc: Avoid overflows when calculating normFactor
  stagefright aacenc: Avoid a division by zero

Author: cco3

media/libstagefright/codecs/aacenc/src/adj_thr.c

@@ -438,7 +438,7 @@ static void correctThresh(PSY_OUT_CHANNEL  psyOutChannel[MAX_CHANNELS],
 	  for (sfb=0; sfb<psyOutChan->maxSfbPerGroup; sfb++) {
         Word32 redThrExp = thrExp[ch][sfbGrp+sfb] + redVal;
 
-        if (((*pahFlag < AH_ACTIVE) || (deltaPe > 0)) && (redThrExp > 0) ) {
+        if (((*pahFlag < AH_ACTIVE) || (deltaPe > 0)) && (redThrExp > 0) && (redThrExp >= *psfbNActiveLines)) {
 
           *psfbPeFactors = (*psfbNActiveLines) * (0x7fffffff / redThrExp);
           normFactor = L_add(normFactor, *psfbPeFactors);
@@ -466,7 +466,7 @@ static void correctThresh(PSY_OUT_CHANNEL  psyOutChannel[MAX_CHANNELS],
         deltaSfbPe = *psfbPeFactors * deltaPe;
 
 		/* thr3(n) = thr2(n)*2^deltaSfbPe/b(n) */
-        if (*psfbNActiveLines > 0) {
+        if (*psfbNActiveLines > 0 && (normFactor* (*psfbNActiveLines)) != 0) {
           /* new threshold */
           Word32 thrFactor;
           sfbEn  = psyOutChan->sfbEnergy[sfbGrp+sfb];