feat: Add Media Session Timestamps and Media Sessions time tracking

[mmustafa-tse]

Summary

Added the following to Roku SDK's Media API

• initializing and calculating the mediaSessionStartTime and mediaSessionEndTime
• added storedPlaybackTime and currentPlaybackStartTimestamp
• update the mediaSessionEndTime on every media session event logged (similar to Web, Android and iOS media SDKs)
• update mediaContentComplete to true when logMediaContentEnd is called
• calculating the mediaContentTimeSpent when logPause and logMediaContentEnd are called

Testing Plan

• Was this tested locally? If not, explain why.
• E2E tested
• Before fix:

- After fix:

Reference Issue (For mParticle employees only. Ignore if you are an outside contributor)

• Closes https://go.mparticle.com/work/SQDSDKS-7260

[BrandonStalnaker]

Just one logic question

[BrandonStalnaker]

Can you explain to me the logic here? It seems like your getting the timestamp of the current date in ms two ways and then adding it together? Is that right or am I misunderstanding?

[mmustafa-tse]

the reason is because with Brightscript there is no way to get the unix timestamp with milliseconds included, only app to seconds, I wanted to match the other media SDKs (and mP in general when dealing with timestamps) to include the unix timestamps including the milliseconds

[BrandonStalnaker]

oh so the (currentTime * 1000) is like the beginning of the day (like midnight) in ms while date.getMilliseconds() gives you like thats days ms?

[rmi22186]

@mmustafa-tse - you are caling the same code 3x throughout this commit. can you make a helper function for getCurrentTimeInMillis which contains this logic to DRY it up?

[BrandonStalnaker]

LGTM