Protect generated C++ headers from multiple includes
Protect generated C++ headers from multiple includes

Change-Id: I1b110cab133366fcc320db31935d8eae454c06f8

cambridgehackers/connectal,chenm001/connectal,csail-csg/connectal,hanw/connectal,8l/connectal,8l/connectal,csail-csg/connectal,chenm001/connectal,chenm001/connectal,cambridgehackers/connectal,8l/connectal,chenm001/connectal,csail-csg/connectal,8l/connectal,cambridgehackers/connectal,8l/connectal,cambridgehackers/connectal,hanw/connectal,hanw/connectal,chenm001/connectal,hanw/connectal,cambridgehackers/connectal,csail-csg/connectal,hanw/connectal,csail-csg/connectal