[ios] TextBadgeView interface, implementation, and unit test stubs

ios/chrome/browser/ui/reading_list/text_badge_view_unittest.mm

+// Copyright 2017 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/reading_list/text_badge_view.h"
+
+#import <Foundation/Foundation.h>
+
+#include "testing/gtest/include/gtest/gtest.h"
+#include "testing/gtest_mac.h"
+
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
+// Tests the badge's intrinsic content size given short display text.
+TEST(TextBadgeViewTest, BadgeSizeShortLabel) {}
+
+// Tests the badge's intrinsic content size given long display text.
+TEST(TextBadgeViewTest, BadgeSizeLongLabel) {}
+
+// Tests that text and layout flip for RTL languages.
+TEST(TextBadgeViewTest, RTL) {}
+
+// Tests that the accessibility label matches the display text.
+TEST(TextBadgeViewTest, Accessibility) {}