Replace get*PhoneAccounts* public API methods with new method (2/3)

Hide getCallCapablePhoneAccounts and getPhoneAccountsSupportingScheme
because a third party app should not be able to see all phone accounts
registered. Replace instead with getPhoneAccountsForPackage(Context)
which will only return the phone accounts registered by a particular package.
Also pass available phone accounts for the user to select from through
Telecom to InCallUI so InCallUI will not be calling the Telecom API
directly to get these accounts.

Bug: 17510811

Change-Id: Ia91972bc4cfa938b743f6b3b165a81d4acd58c45