Implemented new Translate API for purely Objective-C clients.

ios/web_view/public/cwv_translation_language.h

+// 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.
+
+#ifndef IOS_WEB_VIEW_PUBLIC_CWV_TRANSLATION_LANGUAGE_H
+#define IOS_WEB_VIEW_PUBLIC_CWV_TRANSLATION_LANGUAGE_H
+
+#import <ChromeWebView/cwv_export.h>
+#import <Foundation/Foundation.h>
+
+NS_ASSUME_NONNULL_BEGIN
+
+// Represents a single translatable language.
+CWV_EXPORT
+@interface CWVTranslationLanguage : NSObject
+
+- (instancetype)init NS_UNAVAILABLE;
+
+// The ISO language code. en for English, es for Spanish, etc...
+// https://cloud.google.com/translate/docs/languages
+@property(nonatomic, copy, readonly) NSString* languageCode;
+
+// The localized language name.
+@property(nonatomic, copy, readonly) NSString* languageName;
+
+@end
+
+NS_ASSUME_NONNULL_END
+
+#endif  // IOS_WEB_VIEW_PUBLIC_CWV_TRANSLATION_LANGUAGE_H