Update #if guards in base/ that control whether to use stat or stat64 (and friends).

base/platform_file_posix.cc

Index: base/platform_file_posix.cc
diff --git a/base/platform_file_posix.cc b/base/platform_file_posix.cc
index e592da5544e7440f385cda0dd6c99490bef70073..112b6a126d0a2ba77064c1eba1f5149ae0e323ee 100644
--- a/base/platform_file_posix.cc
+++ b/base/platform_file_posix.cc
@@ -21,8 +21,7 @@
 
 namespace base {
 
-#if defined(OS_BSD) || defined(OS_IOS) || (defined(OS_MACOSX) && \
-    MAC_OS_X_VERSION_MIN_REQUIRED < MAC_OS_X_VERSION_10_5)
+#if defined(OS_BSD) || defined(OS_MACOSX)
 typedef struct stat stat_wrapper_t;
 static int CallFstat(int fd, stat_wrapper_t *sb) {
   base::ThreadRestrictions::AssertIOAllowed();