Include what you use for the preparser.

src/dtoa.cc

Index: src/dtoa.cc
diff --git a/src/dtoa.cc b/src/dtoa.cc
index 00233a882933bcd5f5d16123b73cdc8052d8a1fb..a304cf844de9af6d288b5c605174c4b59ce367cc 100644
--- a/src/dtoa.cc
+++ b/src/dtoa.cc
@@ -1,4 +1,4 @@
-// Copyright 2011 the V8 project authors. All rights reserved.
+// Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
@@ -25,18 +25,14 @@
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
-#include <math.h>
-
-#include "../include/v8stdint.h"
-#include "checks.h"
-#include "utils.h"
-
 #include "dtoa.h"
 
 #include "bignum-dtoa.h"
+#include "checks.h"
 #include "double.h"
 #include "fast-dtoa.h"
 #include "fixed-dtoa.h"
+#include "utils.h"
 
 namespace v8 {
 namespace internal {