Check for empty repetitions.

src/regexp-macro-assembler-irregexp.h

Index: src/regexp-macro-assembler-irregexp.h
diff --git a/src/regexp-macro-assembler-irregexp.h b/src/regexp-macro-assembler-irregexp.h
index 871e1e57d304fec74e2315cbaa0f280d819c4579..1167b1d53162c3feafe3974f55c0ff23a2cf361d 100644
--- a/src/regexp-macro-assembler-irregexp.h
+++ b/src/regexp-macro-assembler-irregexp.h
@@ -106,6 +106,7 @@ class RegExpMacroAssemblerIrregexp: public RegExpMacroAssembler {
                                    const Vector<Label*>& destinations);
   virtual void IfRegisterLT(int register_index, int comparand, Label* if_lt);
   virtual void IfRegisterGE(int register_index, int comparand, Label* if_ge);
+  virtual void IfRegisterEqPos(int register_index, Label* if_eq);
 
   virtual IrregexpImplementation Implementation();
   virtual Handle<Object> GetCode(Handle<String> source);