Fixed TypeMemberFunctionImpl to not use clang types directly but use the new...

Fixed TypeMemberFunctionImpl to not use clang types directly but use the new CompilerDecl class to do the job in an abstract way.
Fixed a crash that would happen if you tried to get the name of a constructor or destructor by calling "getDeclName()" instead of calling getName() (which would assert and crash).

Added the ability to get function arguments names from SBFunction.

llvm-svn: 252622