Record overflow cleanup

Add comments and rename one method for clarity

Change-Id: I04a9147e46e88a072256c0211b112d52202419e2
diff --git a/services/audioflinger/AudioFlinger.h b/services/audioflinger/AudioFlinger.h
index 47ceefe..a6d1982 100644
--- a/services/audioflinger/AudioFlinger.h
+++ b/services/audioflinger/AudioFlinger.h
@@ -1365,7 +1365,9 @@
                                      int triggerSession = 0);
             virtual void        stop();
 
-                    bool        overflow() { bool tmp = mOverflow; mOverflow = false; return tmp; }
+                    // clear the buffer overflow flag
+                    void        clearOverflow() { mOverflow = false; }
+                    // set the buffer overflow flag and return previous value
                     bool        setOverflow() { bool tmp = mOverflow; mOverflow = true; return tmp; }
 
                     void        dump(char* buffer, size_t size);
@@ -1380,10 +1382,9 @@
             virtual status_t getNextBuffer(AudioBufferProvider::Buffer* buffer, int64_t pts = kInvalidPTS);
             // releaseBuffer() not overridden
 
-            bool                mOverflow;
+            bool                mOverflow;  // overflow on most recent attempt to fill client buffer
         };
 
-
                 RecordThread(const sp<AudioFlinger>& audioFlinger,
                         AudioStreamIn *input,
                         uint32_t sampleRate,