Remove ChromeBrowserProvider::GetLiveTabContextProvider() method.

ios/public/provider/chrome/browser/sessions/live_tab_context_provider.h

-// Copyright 2014 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_PUBLIC_PROVIDER_CHROME_BROWSER_SESSIONS_LIVE_TAB_CONTEXT_PROVIDER_H_
-#define IOS_PUBLIC_PROVIDER_CHROME_BROWSER_SESSIONS_LIVE_TAB_CONTEXT_PROVIDER_H_
-
-#include <stdint.h>
-
-namespace sessions {
-class LiveTab;
-class LiveTabContext;
-}
-
-namespace ios {
-
-class ChromeBrowserState;
-
-// A class that allows retrieving a sessions::LiveTabContext.
-class LiveTabContextProvider {
- public:
-  virtual ~LiveTabContextProvider() {}
-
-  // Creates a new context.
-  virtual sessions::LiveTabContext* Create(
-      ios::ChromeBrowserState* browser_state) = 0;
-
-  // Retrieves the context with the given ID, if one exists.
-  virtual sessions::LiveTabContext* FindContextWithID(int32_t desired_id) = 0;
-
-  // Retrieves the context for the given tab, if one exists.
-  virtual sessions::LiveTabContext* FindContextForTab(
-      const sessions::LiveTab* tab) = 0;
-};
-
-}  // namespace ios
-
-#endif  // IOS_PUBLIC_PROVIDER_CHROME_BROWSER_SESSIONS_LIVE_TAB_CONTEXT_PROVIDER_H_