[ObjC ARC] Converts ios/chrome/browser/ui/autofill:autofill to ARC.

ios/chrome/browser/ui/autofill/storage_switch_tooltip.mm

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #import "ios/chrome/browser/ui/autofill/storage_switch_tooltip.h"
 
 #include "base/logging.h"
 #include "components/strings/grit/components_strings.h"
 #import "ios/third_party/material_roboto_font_loader_ios/src/src/MaterialRobotoFontLoader.h"
 #include "ui/base/l10n/l10n_util.h"
 
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
 namespace {
 
 const CGFloat kCornerRadius = 2.0f;
 const CGFloat kFontSize = 12.0f;
 const CGFloat kInset = 8.0f;
 
 }  // namespace
 
 @implementation StorageSwitchTooltip
 
@@ skipping 39 matching lines @@
 
   return rect;
 }
 
 - (void)drawTextInRect:(CGRect)rect {
   UIEdgeInsets insets = {kInset, kInset, kInset, kInset};
   [super drawTextInRect:UIEdgeInsetsInsetRect(rect, insets)];
 }
 
 @end