Issue 2071329: audio track is shorter than video track for video capture on sholes

Add API to retrieve number of frames dropped by audio input kernel driver.

Submitted on behalf of Masaki Sato <masaki.sato@motorola.com>
diff --git a/libs/audioflinger/AudioHardwareGeneric.h b/libs/audioflinger/AudioHardwareGeneric.h
index 95c7ea3..aa4e78d 100644
--- a/libs/audioflinger/AudioHardwareGeneric.h
+++ b/libs/audioflinger/AudioHardwareGeneric.h
@@ -88,6 +88,7 @@
     virtual status_t    standby() { return NO_ERROR; }
     virtual status_t    setParameters(const String8& keyValuePairs);
     virtual String8     getParameters(const String8& keys);
+    virtual unsigned int  getInputFramesLost() const { return 0; }
 
 private:
     AudioHardwareGeneric *mAudioHardware;