Added test cases for public api.

Added test cases for public api.

Coverage of public API methods showed that some methods had no
test cases. Have added test cases for all relevant methods.

Reminder: No C++ method coverage can be 100% complete ( compiler
generated virtual destructors cannot always be called ).

Change-Id: Ia3dc12b5e8262ea1e20c17141378d2a2f3c91b8e
Signed-off-by: David Steele <david.steele@samsung.com>