Add AssertIOAllowed check in the SysInfo::AmountOfFreeDiskSpace.

base/sys_info_win.cc

Index: base/sys_info_win.cc
diff --git a/base/sys_info_win.cc b/base/sys_info_win.cc
index 78c773f2d99923866f310dbec1793b0320f9bd22..87ce66d82b5c75deeac08875bd1aa3fddbf394dd 100644
--- a/base/sys_info_win.cc
+++ b/base/sys_info_win.cc
@@ -10,6 +10,7 @@
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/stringprintf.h"
+#include "base/threading/thread_restrictions.h"
 #include "base/win/windows_version.h"
 
 namespace base {
@@ -36,6 +37,8 @@ int64 SysInfo::AmountOfPhysicalMemory() {
 
 // static
 int64 SysInfo::AmountOfFreeDiskSpace(const FilePath& path) {
+  base::ThreadRestrictions::AssertIOAllowed();
+
   ULARGE_INTEGER available, total, free;
   if (!GetDiskFreeSpaceExW(path.value().c_str(), &available, &total, &free)) {
     return -1;