Move UBSan warnings from a blacklist to the source

webrtc/common_audio/signal_processing/division_operations.c

Index: webrtc/common_audio/signal_processing/division_operations.c
diff --git a/webrtc/common_audio/signal_processing/division_operations.c b/webrtc/common_audio/signal_processing/division_operations.c
index eaa06a1ff9299c20b7ebdcc5ed9ba30303dd5c50..2d420525bab1c29accf5a144130a4ec5abeddade 100644
--- a/webrtc/common_audio/signal_processing/division_operations.c
+++ b/webrtc/common_audio/signal_processing/division_operations.c
@@ -22,6 +22,7 @@
  */
 
 #include "webrtc/common_audio/signal_processing/include/signal_processing_library.h"
+#include "webrtc/rtc_base/sanitizer.h"
 
 uint32_t WebRtcSpl_DivU32U16(uint32_t num, uint16_t den)
 {
@@ -97,7 +98,8 @@ int32_t WebRtcSpl_DivResultInQ31(int32_t num, int32_t den)
     return div;
 }
 
-int32_t WebRtcSpl_DivW32HiLow(int32_t num, int16_t den_hi, int16_t den_low)
+int32_t RTC_NO_SANITIZE("signed-integer-overflow")  // bugs.webrtc.org/5486
+WebRtcSpl_DivW32HiLow(int32_t num, int16_t den_hi, int16_t den_low)
 {
     int16_t approx, tmp_hi, tmp_low, num_hi, num_low;
     int32_t tmpW32;
@@ -110,6 +112,7 @@ int32_t WebRtcSpl_DivW32HiLow(int32_t num, int16_t den_hi, int16_t den_low)
     // tmpW32 = den * approx
 
     tmpW32 = (int32_t)0x7fffffffL - tmpW32; // result in Q30 (tmpW32 = 2.0-(den*approx))
+    // UBSan: 2147483647 - -2 cannot be represented in type 'int'
 
     // Store tmpW32 in hi and low format
     tmp_hi = (int16_t)(tmpW32 >> 16);