Display error when failed to link some contacts

SIM Raw contacts are unlinkable on some OEM devices
like samsung s4 and s5. Their native contact app disables
the feature but we still support it for Nexus and newer
devices like s7. Show error toast when failing to link
these contacts instead of showing a success toast.

Test: manual
 - Link "unlinkable" contacts and see new error message
 - Link linkable contacts and see success path
 - Link sim contacts and see error message on s5

Bug:28637870
Bug:28622373

Change-Id: Ia124f4f2a842c8b8ad3b57367a19edea9fc0fbab