I experienced this same error after my hosting company updated our PHP version from 7.0.x to 7.1.x. They assumed that since it was a minor update, it should be compatible with previous versions. They were wrong: here’s a list of the incompatibilities from the migration page.
In this particular case code that would previously throw a warning about the lack of parameters for a function call is now throwing the fatal error in the OP’s question.
The solution is obviously to provide the appropriate parameters as the other answers have indicated.