Otherwise, we end up discarding stream data messages, and our decode
can become corrupted, notably on Chrome.
This way, we should not lose any messages while we are waiting for
source buffer creation.
Previously, we sent them strictly upon receipt. However, receiving
is fast; by adding in some of the processing time (i.e. queueing and
so on), we encourage the adaptive rate control to slow down.
This helps video playback do a slightly better job of keeping up
in the browser. It's not a dramatic effect, but enough to start making
video playback almost tolerable.
Also converts the display cache from an array to an object. This is to help enforce proper sparceness of the data as well as make it easier to reliably fully delete a given cache entry without affecting access to the remaining entries.
The first approach is to use a moving image to simulate the cursor.
This does not work well, so a second approach, involving static
cursors is provided. That requires a site administrator to precreate
all the cursors that can be used by a particular application set.
A warning message strongly suggests using a different browser as well.
