Refactor the process of choosing validators.

src/trusted/validator/x86/ncval_seg_sfi/ncdecode.c

Index: src/trusted/validator/x86/ncval_seg_sfi/ncdecode.c
diff --git a/src/trusted/validator/x86/ncval_seg_sfi/ncdecode.c b/src/trusted/validator/x86/ncval_seg_sfi/ncdecode.c
index e1e3ccfb3564b4c312b5ce923b3938bcd59a5d28..07e49a35f030673595a43d6321b1da6ad665f427 100644
--- a/src/trusted/validator/x86/ncval_seg_sfi/ncdecode.c
+++ b/src/trusted/validator/x86/ncval_seg_sfi/ncdecode.c
@@ -685,10 +685,12 @@ static Bool NullNCDecoderStatePairAction(struct NCDecoderStatePair* tthis,
 
 void NCDecoderStatePairConstruct(NCDecoderStatePair* tthis,
                                  NCDecoderState* old_dstate,
-                                 NCDecoderState* new_dstate) {
+                                 NCDecoderState* new_dstate,
+                                 const NaClCopyInstructionFunc copy_func) {
   tthis->old_dstate = old_dstate;
   tthis->new_dstate = new_dstate;
   tthis->action_fn = NullNCDecoderStatePairAction;
+  tthis->copy_func = copy_func;
 }
 
 void NCDecoderStatePairDestruct(NCDecoderStatePair* tthis) {