Split //blimp/client/core to relevant parts.

blimp/client/public/blimp_contents.h

-// Copyright 2016 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 BLIMP_CLIENT_PUBLIC_BLIMP_CONTENTS_H_
-#define BLIMP_CLIENT_PUBLIC_BLIMP_CONTENTS_H_
-
-#include "base/macros.h"
-#include "base/supports_user_data.h"
-#include "url/gurl.h"
-
-namespace blimp {
-namespace client {
-
-class BlimpContentsObserver;
-class BlimpNavigationController;
-
-// BlimpContents is the core class in //blimp/client/core. It renders web pages
-// from an engine in a rectangular area.
-// It enables callers to control the blimp engine through the use of the
-// navigation controller.
-class BlimpContents : public base::SupportsUserData {
- public:
-  // Retrives the navigation controller that controls all navigation related
-  // to this BlimpContents.
-  virtual BlimpNavigationController& GetNavigationController() = 0;
-
-  // Enables adding and removing observers to this BlimpContents.
-  virtual void AddObserver(BlimpContentsObserver* observer) = 0;
-  virtual void RemoveObserver(BlimpContentsObserver* observer) = 0;
-
- protected:
-  BlimpContents() {}
-
- private:
-  DISALLOW_COPY_AND_ASSIGN(BlimpContents);
-};
-
-}  // namespace client
-}  // namespace blimp
-
-#endif  // BLIMP_CLIENT_PUBLIC_BLIMP_CONTENTS_H_