Switch to standard integer types in ash/.

ash/system/chromeos/rotation/tray_rotation_lock_unittest.cc

Index: ash/system/chromeos/rotation/tray_rotation_lock_unittest.cc
diff --git a/ash/system/chromeos/rotation/tray_rotation_lock_unittest.cc b/ash/system/chromeos/rotation/tray_rotation_lock_unittest.cc
index 6ff259f5934b8ff5f1822060aee699e97bda2199..d389082845acca856f90778743378bb197e16ff8 100644
--- a/ash/system/chromeos/rotation/tray_rotation_lock_unittest.cc
+++ b/ash/system/chromeos/rotation/tray_rotation_lock_unittest.cc
@@ -243,7 +243,7 @@ TEST_F(TrayRotationLockTest, PerformActionOnDefaultView) {
 // Tests that when the tray is created without the internal display being known,
 // that it will still display correctly once the internal display is known.
 TEST_F(TrayRotationLockTest, InternalDisplayNotAvailableAtCreation) {
-  int64 internal_display_id = gfx::Display::InternalDisplayId();
+  int64_t internal_display_id = gfx::Display::InternalDisplayId();
   TearDownViews();
   gfx::Display::SetInternalDisplayId(gfx::Display::kInvalidDisplayID);