[cs] Correctly set hxgen of an abstract / abstract implementation to the underlying type. Closes #3248
[java/cs] Recurse into cases expressions the SwitchToIf handler. Closes #3315
[java/cs] Fixed bad type parameter caught from already followed tf_args/tf_type; Closes #2889
[java] Create speciailized Lib.array versions for basic types. Closes #2927
[java/cs] Added test for #2941