Fix building with 2.065.

As reported [here](http://forum.dlang.org/thread/vgeouugkicutpiyvxvai@forum.dlang.org).

```
C:\dev\projects\DustMite>dmd dustmite.d splitter.d
splitter.d(261): Error: delegate splitter.DSplitter.__lambda46 function literals cannot
be class members
CTFE: ErrorExp in splitter.d(286)
Assertion failure: '0' on line 310 in file 'interpret.c'
```