Fix to mute/unmute properly while adding a call

Call setMuteInternal instead of setMute while adding
call to an existing active call.

Change-Id: I245f966c6929b5d1a92b2b7dff1f9e79e2a8d04a
CRs-Fixed: 650135
TeleService: Update mute state accordingly after adding call

The mute state of sub1 that is stored in the mute table isn't restored to
the previous state when the second call(on sub2) is connected.

Restore the mute state for sub1 in CallButtonPresenter#refreshMuteState().

CRs-Fixed: 660470

Change-Id: Id9e0bf9c7e41ccb7cf210f8adfa0938ead650f74
MSIM(DSDA): Use conversation sub to maintain LCH properly

Use conversation sub to maintain LCH properly

Change-Id: I2307d04a9e32a43234a5e56d995e20db464a6187
CRs-Fixed: 659123