m_timeOfBufferingMonitor is initialized in SourceBuffer at creation time. If the first call to monitorBufferingRate() takes too much to happen for whatever reason (eg: because the webpage takes too much to perform the first append), the computed interval is already going to be too big and generate an artificially low m_averageBufferRate.
Pull request: https://github.com/WebKit/WebKit/pull/10793
<rdar://problem/106358375>
Committed 261328@main (1581c8aa2d3c): <https://commits.webkit.org/261328@main> Reviewed commits have been landed. Closing PR #10793 and removing active labels.