Currently PageThrottler keeps a track of audible plugin activity and HTML media element activity separately. Audible plugin activity also gets an extra 5s hysteresis applied, so that after audio playback has completed there is a chance to queue up more audio before timer throttling kicks in. HTML audio does not get this grace. Funnel both together into a single activity flag, such that the hysteresis is applied to both.
Created attachment 272705 [details] Fix
Transmitting file data ... Committed revision 197480.