Merge "MediaMetrics: Change the duplicate logging suffix"

// followed by one or more characters in the range [a-zA-Z0-9_.].

// Special symbols such as !@#$%^&*()[]{}<>,:;'"\/?|+-=~ are reserved.

//

// A property that ends with a ! will have duplicate values listed instead

// Properties within this header should include special suffixes like '#'

// directly in the string for brevity.  Code outside of this header should

// use the macro constant for the special symbols for searchability.

// Any property that ends with a # will have duplicate values listed instead

// of suppressed in the Time Machine.

//

#define AMEDIAMETRICS_PROP_SUFFIX_CHAR_DUPLICATES_ALLOWED '#'

#define AMEDIAMETRICS_PROP_AUXEFFECTID    "auxEffectId"    // int32 (AudioTrack)

#define AMEDIAMETRICS_PROP_CHANNELCOUNT   "channelCount"   // int32

#define AMEDIAMETRICS_PROP_CHANNELMASK    "channelMask"    // int32

#define AMEDIAMETRICS_PROP_CONTENTTYPE    "contentType"    // string attributes (AudioTrack)

#define AMEDIAMETRICS_PROP_DURATIONNS     "durationNs"     // int64 duration time span

#define AMEDIAMETRICS_PROP_ENCODING       "encoding"       // string value of format

#define AMEDIAMETRICS_PROP_EVENT          "event!"         // string value (often func name)

#define AMEDIAMETRICS_PROP_EVENT          "event#"         // string value (often func name)

// TODO: fix inconsistency in flags: AudioRecord / AudioTrack int32,  AudioThread string

#define AMEDIAMETRICS_PROP_FLAGS          "flags"

 * The TimeMachine is used to record timing changes of MediaAnalyticItem

 * properties.

 *

 * Any URL that ends with '!' will have a time sequence that keeps duplicates.

 * Any URL that ends with '#' (AMEDIAMETRICS_PROP_SUFFIX_CHAR_DUPLICATES_ALLOWED)

 * will have a time sequence that keeps duplicates.

 *

 * The TimeMachine is NOT thread safe.

 */

            auto& timeSequence = mPropertyMap[property];

            Elem el{std::forward<T>(e)};

            if (timeSequence.empty()           // no elements

                    || property.back() == '!'  // keep duplicates TODO: remove?

                    || property.back() == AMEDIAMETRICS_PROP_SUFFIX_CHAR_DUPLICATES_ALLOWED

                    || timeSequence.rbegin()->second != el) { // value changed

                timeSequence.emplace(time, std::move(el));

            }