Intern strings used in Sensor information.

By creating a local 'interning map', Sensor information, such as: name, vendor,
stringType, and requirePermissions; 92 string objects are not needed anymore.
This frees ~6KB of memory in all processes accessing SensorManager.

Change-Id: Idfdc98160363bec844c34fc3b71f5e8d7843a7be
2 files changed