Update V8 to r4730 as required by WebKit r60469
diff --git a/src/ia32/cpu-ia32.cc b/src/ia32/cpu-ia32.cc
index 2107ad9..b15140f 100644
--- a/src/ia32/cpu-ia32.cc
+++ b/src/ia32/cpu-ia32.cc
@@ -33,6 +33,8 @@
 
 #include "v8.h"
 
+#if defined(V8_TARGET_ARCH_IA32)
+
 #include "cpu.h"
 #include "macro-assembler.h"
 
@@ -77,3 +79,5 @@
 }
 
 } }  // namespace v8::internal
+
+#endif  // V8_TARGET_ARCH_IA32