base

Use PhoneBase in the phone list.

For bug 3001613.

Only use PhoneBase (not PhoneProxy) in CallManager.

Both PhoneBase and PhoneProxy implement Phone interface,

such as dial(). The real implementation, for

example in GSM,  is in GSMPhone extending from PhoneBase.

So that foregroundCall.getPhone() returns GSMPhone obj. On the other hand,

PhoneFactory.getDefaultPhone() returns PhoneProxy obj, which has a class

member of GSMPhone.

Therefore for phone returned by PhoneFacotry, which is used by PhoneApp,

        phone.getForegroundCall().getPhone() != phone

Change-Id: I8a304098dd86762aaee56fb3c8b76c883e8c9a4f