Bug 745272: Replace comparison of unsigned value >=0 with a useful comparison. r=humph r=cpearce

content/media/nsAudioAvailableEventManager.cpp

@@ -165,6 +165,9 @@ void nsAudioAvailableEventManager::QueueWrittenAudioData(AudioDataValue* aAudioD
       signalBuffer[i] = MOZ_CONVERT_AUDIO_SAMPLE(audioData[i]);
     }
     audioData += signalBufferTail;
+
+    NS_ASSERTION(audioDataLength >= signalBufferTail,
+                 "audioDataLength about to wrap past zero to +infinity!");
     audioDataLength -= signalBufferTail;
 
     if (mPendingEvents.Length() > 0) {
@@ -192,7 +195,6 @@ void nsAudioAvailableEventManager::QueueWrittenAudioData(AudioDataValue* aAudioD
     mSignalBuffer = new float[currentBufferSize];
     mSignalBufferPosition = 0;
     signalBufferTail = currentBufferSize;
-    NS_ASSERTION(audioDataLength >= 0, "Past new signal data length.");
   }
 
   NS_ASSERTION(mSignalBufferPosition + audioDataLength < mSignalBufferLength,