Fix org.hbbtv_DA541510 and org.hbbtv_DA541160

[danips]

• Rewind interval needs to be bigger so the frame has time to get updated on screen.
• speed attribute needs to get updated when simulating rewind.
• PlaySpeedChanged needs to be triggered when simulating rewind.
• A transition to PLAY_STATE_PLAYING is required when the seek operation is finished if not paused (priv.targetSpeed > 0). Otherwise it stays in PLAY_STATE_BUFFERING.
• timeupdate events need to be ignored when simulating rewind.
• __orb_onplayspeedchanged__ events needs to be ignored when simulating rewind.

[danips]

I've just tested the seek() operation doesn't experiment any change by running all the seek() tests I could find to check the same results are obtained:

• org.hbbtv_00003540
• org.hbbtv_00003560
• org.hbbtv_00003580
• org.hbbtv_00003600
• org.hbbtv_00003980
• org.hbbtv_DA541220
• org.hbbtv_DA541230
• org.hbbtv_DA541240
• org.hbbtv_DA541250
• org.hbbtv_DASH-TIMELINE0050
• org.hbbtv_MEDIAPLAYER0010
• org.hbbtv_MEDIAPLAYER0020
• org.hbbtv_MEDIAPLAYER0030
• org.hbbtv_MEDIAPLAYER0040
• tv.oipf_DAE-CE_HTML_DEV-042
• tv.oipf_DAE-MEDIA_PLAYBACK-027
• tv.oipf_DAE-MEDIA_PLAYBACK-028
• tv.oipf_DAE-MEDIA_PLAYBACK-029
• tv.oipf_DAE-MEDIA_PLAYBACK-030