Fixed debugger display variable reference in Block class.
Fixed debugger display variable reference in Block class.

Fixes https://github.com/mono/CppSharp/issues/1113
zillemarco/CppSharp,mono/CppSharp,mono/CppSharp,zillemarco/CppSharp,ddobrev/CppSharp,mono/CppSharp,zillemarco/CppSharp,mono/CppSharp,mono/CppSharp,zillemarco/CppSharp,ddobrev/CppSharp,mono/CppSharp,ddobrev/CppSharp,ddobrev/CppSharp,ddobrev/CppSharp,zillemarco/CppSharp