Bug 946502. Part 5: A ViewportFrame with a displayport on the root element needs to be an animated geometry root. r=mattwoodrow

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extra : rebase_source : 15005e1ef96836deed4f6910a113be5f8a0b3316
Merge m-c to m-i
Bug 906752 - Disable test_audioBufferSourceNodeOffset.html on B2G opt for frequent failures.
Bug 844473 - Honor mozdisallowselectionprint and moznomarginboxes in print preview and use child document. r=roc
Bug 964197 - Add frame duration for synchronization. r=cpearce
Bug 777574 - Skip quickCheckAPI-B3.html on Linux Mesa since it fails on ASan tests all the time
Bug 964379 - Add logging to figure out what's breaking xpcshell on comm-central on OSX 10.6.
Bug 777574 - Skip quickCheckAPI-B4.html on Linux Mesa since it fails on ASan tests all the time
b=966800 don't ignore blocking changes when another stream is finishing or underrunning r=roc

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extra : transplant_source : %7C%C3B%08%3E%D2%B2%93%BC%811%22%D1%27%95%AF%BD%D1eB
b=966867 don't overwrite preferred sample rate with default r=kinetik

--HG--
extra : transplant_source : /S%9D/%BC%80%E0%E3%C3%11%E7%EA%D4%BB%F3%D7%AD%06%B7%25
b=966867 use internal linkage for GetSampleRateForAudioContext r=kinetik

--HG--
extra : transplant_source : t%F5%2A%A2%ADbI%40%A3%0E%9FS%D1%FCC%0B%1B%3E%0A%9B
merge mozilla-inbound to mozilla-central