Fix for KT-3969: Codegen fails on unary calls with default arguments

  #KT-3969 Fixed
Fixes for KT-4991: Prefix/postfix expressions resolved to local extensions are not supported in codegen;
KT-4989: Verify error on local functions and extensions;
KT-4987: NegativeArraySizeException on local extension convention function on nullable Int

  #KT-4991 Fixed
  #KT-4989 Fixed
  #KT-4987 Fixed
Clean