[Interpreter] Fix a register allocation bug and add a DCHECK.

src/interpreter/bytecode-array-builder.h

Index: src/interpreter/bytecode-array-builder.h
diff --git a/src/interpreter/bytecode-array-builder.h b/src/interpreter/bytecode-array-builder.h
index 15ff07e93d056db3ce4624854a95045b75128c4e..4ee7be2b5f99034e37ad4d16f44a1b14ab7a3b53 100644
--- a/src/interpreter/bytecode-array-builder.h
+++ b/src/interpreter/bytecode-array-builder.h
@@ -316,6 +316,8 @@ class TemporaryRegisterScope {
   void PrepareForConsecutiveAllocations(size_t count);
   Register NextConsecutiveRegister();
 
+  bool RegisterIsAllocatedInThisScope(Register reg) const;
+
  private:
   void* operator new(size_t size);
   void operator delete(void* p);