fad0ce59e9 tests: Fail if RPC has been added without tests (MarcoFalke)
Pull request description:
Need to be run with --coverage
ACKs for commit fad0ce:
ryanofsky: utACK fad0ce59e9154f9b7e61907a71c740a942c60282. New comment in travis.yml is the only change since last review.
Tree-SHA512: b53632dfe9865ec06991bfcba2fd67238bebbb866b355f09624eaf233257b2bca902caac6c24abb358b2f4c1c43f28ca75e30982765911e1a117102df65276d9
Backport of Core PR15943