Reduce indentation in AudioIO

Flipped some conditions and used if else-if to reduce the indentation in code.
This makes the code more readable.  No change in functionality.
Also created UpdateTimePositions() and made some bool functions void.

new variable mMaxFramesOutput used to communicate positional change.

src/AudioIO.h

@@ -333,20 +333,22 @@ public:
    void ComputeMidiTimings(
       const PaStreamCallbackTimeInfo *timeInfo,
       unsigned long framesPerBuffer);
-   void CheckSoundActivatedRecordingLevel();
+   void CheckSoundActivatedRecordingLevel(const void *inputBuffer);
    bool FillOutputBuffers(
-      const void *inputBuffer, 
       void *outputBuffer,
       unsigned long framesPerBuffer,
       float * tempFloats, float *outputMeterFloats
    );
-   bool FillInputBuffers(
+   void FillInputBuffers(
       const void *inputBuffer, 
       unsigned long framesPerBuffer,
       const PaStreamCallbackFlags statusFlags,
       float * tempFloats
    );
-   bool DoPlaythrough(
+   void UpdateTimePosition(
+      unsigned long framesPerBuffer
+   );
+   void DoPlaythrough(
       const void *inputBuffer, 
       void *outputBuffer,
       unsigned long framesPerBuffer,
@@ -493,6 +495,7 @@ public:
    double              mFactor;
    /// Audio playback rate in samples per second
    double              mRate;
+   unsigned long       mMaxFramesOutput; // The actual number of frames output.
 
    double              mSeek;
    double              mPlaybackRingBufferSecs;