[regexp] do not include irregexp interpreter by default.

src/regexp/regexp-macro-assembler-irregexp.h

Index: src/regexp/regexp-macro-assembler-irregexp.h
diff --git a/src/regexp/regexp-macro-assembler-irregexp.h b/src/regexp/regexp-macro-assembler-irregexp.h
index eddca4dc8f262d2fd926f5b928c4ff222ac604f9..204f7e24cbed71a53ecadfae07bd3411e9782162 100644
--- a/src/regexp/regexp-macro-assembler-irregexp.h
+++ b/src/regexp/regexp-macro-assembler-irregexp.h
@@ -5,13 +5,13 @@
 #ifndef V8_REGEXP_REGEXP_MACRO_ASSEMBLER_IRREGEXP_H_
 #define V8_REGEXP_REGEXP_MACRO_ASSEMBLER_IRREGEXP_H_
 
+#ifdef V8_INTERPRETED_REGEXP
+
 #include "src/regexp/regexp-macro-assembler.h"
 
 namespace v8 {
 namespace internal {
 
-#ifdef V8_INTERPRETED_REGEXP
-
 // A light-weight assembler for the Irregexp byte code.
 class RegExpMacroAssemblerIrregexp: public RegExpMacroAssembler {
  public:
@@ -131,9 +131,9 @@ class RegExpMacroAssemblerIrregexp: public RegExpMacroAssembler {
   DISALLOW_IMPLICIT_CONSTRUCTORS(RegExpMacroAssemblerIrregexp);
 };
 
-#endif  // V8_INTERPRETED_REGEXP
-
 }  // namespace internal
 }  // namespace v8
 
+#endif  // V8_INTERPRETED_REGEXP
+
 #endif  // V8_REGEXP_REGEXP_MACRO_ASSEMBLER_IRREGEXP_H_