Remove @Override annotation for implementing interface methods.

Mockito is configured with 1.5 source/target compatibility (according to
build.gradle). In Java 5 it's illegal to specify the @Override
annotation on method implementations based on interface. This change
removes those in order to have the Mockito compile on 1.5 without
compilation errors.

Signed-off-by: Gunnar Wagenknecht <gunnar@wagenknecht.org>
Fix test failure by resetting counter before executing test.

In order for this test to succeed, the counter must be 0 at the
beginning. 

Signed-off-by: Gunnar Wagenknecht <gunnar@wagenknecht.org>