Bug 1090919 - Fix audio problem when mediaserver is restarted. r=mwu

When mediaserver is restarted AudioPolicyService needs to be
recreated when mediasrever is fully started.
Bug 1078125 - fix RtspMediaCodecReader::ReadMetadata, start the network streaming before ReadMetadata and enable play-out delay. r=cpearce, r=ethan
Bug 968750 - B2G MMS: MmsDeliveryInfo.readStatus saved as "pending" read status when toggled. r=echen