[ios] Adds a LocationBarController interface.

ios/shared/chrome/browser/ui/omnibox/location_bar_controller.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_SHARED_CHROME_BROWSER_UI_OMNIBOX_LOCATION_BAR_CONTROLLER_H_
+#define IOS_SHARED_CHROME_BROWSER_UI_OMNIBOX_LOCATION_BAR_CONTROLLER_H_
+
+#include "ios/shared/chrome/browser/ui/omnibox/web_omnibox_edit_controller.h"
+
+class OmniboxView;
+
+// C++ object that wraps an OmniboxViewIOS and serves as its
+// OmniboxEditController.  LocationBarController bridges between the edit view
+// and the rest of the browser and manages text field decorations (location
+// icon, security icon, etc.).
+class LocationBarController : public WebOmniboxEditController {
+ public:
+  LocationBarController();
+  ~LocationBarController() override;
+
+  // Called when toolbar state is updated.
+  virtual void OnToolbarUpdated() = 0;
+
+  // Resign omnibox first responder and end edit view editing.
+  virtual void HideKeyboardAndEndEditing() = 0;
+
+  // Tells the omnibox if it can show the hint text or not.
+  virtual void SetShouldShowHintText(bool show_hint_text) = 0;
+
+  // Returns a pointer to the text entry view.
+  virtual const OmniboxView* GetLocationEntry() const = 0;
+  virtual OmniboxView* GetLocationEntry() = 0;
+
+  // True if the omnibox text field is showing a placeholder image in its left
+  // view while it's collapsed (i.e. not in editing mode).
+  virtual bool IsShowingPlaceholderWhileCollapsed() = 0;
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(LocationBarController);
+};
+
+#endif  // IOS_SHARED_CHROME_BROWSER_UI_OMNIBOX_LOCATION_BAR_CONTROLLER_H_