No need to flood receivers with progress events since they are basically
always going to the UI, and the UI will only refresh every so often. If
the refresh rate is 50Hz, then that's every 20ms. 100ms seems to make a
smooth enough progress bar, and saves some CPU time. This becomes more
important if there are multiple downloads happening in the background, like
if we make DownloaderService support parallel downloads from different repos
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