Merge "AudioTrack: Fix callback timing if less than one AF mixer period." into qt-dev

                    const nsecs_t timeNow = systemTime();

                    ns = max((nsecs_t)0, ns - (timeNow - timeAfterCallbacks));

                }

                nsecs_t myns = framesToNanoseconds(mRemainingFrames - avail, sampleRate, speed);

                if (ns < 0 /* NS_WHENEVER */ || myns < ns) {

                    ns = myns;

                // delayNs is first computed by the additional frames required in the buffer.

                nsecs_t delayNs = framesToNanoseconds(

                        mRemainingFrames - avail, sampleRate, speed);

                // afNs is the AudioFlinger mixer period in ns.

                const nsecs_t afNs = framesToNanoseconds(mAfFrameCount, mAfSampleRate, speed);

                // If the AudioTrack is double buffered based on the AudioFlinger mixer period,

                // we may have a race if we wait based on the number of frames desired.

                // This is a possible issue with resampling and AAudio.

                //

                // The granularity of audioflinger processing is one mixer period; if

                // our wait time is less than one mixer period, wait at most half the period.

                if (delayNs < afNs) {

                    delayNs = std::min(delayNs, afNs / 2);

                }

                // adjust our ns wait by delayNs.

                if (ns < 0 /* NS_WHENEVER */ || delayNs < ns) {

                    ns = delayNs;

                }

                return ns;

            }