Implemented new Translate API for purely Objective-C clients.

ios/web_view/internal/translate/cwv_translation_controller_internal.h

Index: ios/web_view/internal/translate/cwv_translation_controller_internal.h
diff --git a/ios/web_view/internal/translate/cwv_translation_controller_internal.h b/ios/web_view/internal/translate/cwv_translation_controller_internal.h
new file mode 100644
index 0000000000000000000000000000000000000000..6b74d554526a7c6e861096d4bec3815026a00076
--- /dev/null
+++ b/ios/web_view/internal/translate/cwv_translation_controller_internal.h
@@ -0,0 +1,43 @@
+// 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_INTERNAL_TRANSLATE_CWV_TRANSLATION_CONTROLLER_INTERNAL_H
+#define IOS_WEB_VIEW_INTERNAL_TRANSLATE_CWV_TRANSLATION_CONTROLLER_INTERNAL_H
+
+#import "ios/web_view/public/cwv_translation_controller.h"
+
+#include <string>
+
+#include "components/translate/core/browser/translate_step.h"
+#include "components/translate/core/common/translate_errors.h"
+
+namespace web {
+class WebState;
+}
+
+NS_ASSUME_NONNULL_BEGIN
+
+// Some internal methods needed to hide any C++ details.
+@interface CWVTranslationController ()
+
+// Set to create a new translate stack under the new webState.
+@property(nonatomic, assign) web::WebState* webState;
+
+// Called to keep this class informed of the current translate progress.
+// |step| the state of current translation.
+// |sourceLanguage| the source language associated with the current |step|.
+// |targetLanguage| the target langauge associated with the current |step|.
+// |errorType| the error, if any for the current |step|.
+// |triggeredFromMenu| should be true if this was a result from user action.
+- (void)updateTranslateStep:(translate::TranslateStep)step
+             sourceLanguage:(const std::string&)sourceLanguage
+             targetLanguage:(const std::string&)targetLanguage
+                  errorType:(translate::TranslateErrors::Type)errorType
+          triggeredFromMenu:(bool)triggeredFromMenu;
+
+@end
+
+NS_ASSUME_NONNULL_END
+
+#endif  // IOS_WEB_VIEW_INTERNAL_TRANSLATE_CWV_TRANSLATION_CONTROLLER_INTERNAL_H