Properly handle delegate literals in nested context code.

They can be demoted to function literals without being static.

GitHub: Fixes ldc-developers#447.

gen/nested.cpp

@@ -317,7 +317,7 @@ static void DtoCreateNestedContextType(FuncDeclaration* fd) {
 
         LLStructType* innerFrameType = NULL;
         unsigned depth = -1;
-        if (!fd->isStatic()) {
+        if (fd->isNested()) {
             if (FuncDeclaration* parfd = getParentFunc(fd, true)) {
                 // Make sure the parent has already been analyzed.
                 DtoCreateNestedContextType(parfd);