Add mapping string for call reject cause code 26.

Mapping string for the specified disconnect cause.
Show a toast string "non-selected user clearing"
for cause code 26

Change-Id: If11852d6a4ea27d4279e1204909bbfc0b9aa41b0
CRs-Fixed: 801884

Conflicts:
	telephony/java/android/telephony/DisconnectCause.java