Revert "mac: Allow Chrome to hand off its active URL to other devices."

chrome/browser/ui/cocoa/handoff_active_url_observer.cc

Index: chrome/browser/ui/cocoa/handoff_active_url_observer.cc
diff --git a/chrome/browser/ui/cocoa/handoff_active_url_observer.cc b/chrome/browser/ui/cocoa/handoff_active_url_observer.cc
deleted file mode 100644
index 592a757408ab6233c7904badf30ee0b32485b2d2..0000000000000000000000000000000000000000
--- a/chrome/browser/ui/cocoa/handoff_active_url_observer.cc
+++ /dev/null
@@ -1,124 +0,0 @@
-// 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.
-
-#include "chrome/browser/ui/cocoa/handoff_active_url_observer.h"
-
-#include "base/logging.h"
-#include "chrome/browser/ui/browser_finder.h"
-#include "chrome/browser/ui/browser_list.h"
-#include "chrome/browser/ui/cocoa/handoff_active_url_observer_delegate.h"
-#include "chrome/browser/ui/tabs/tab_strip_model.h"
-#include "content/public/browser/web_contents.h"
-
-HandoffActiveURLObserver::HandoffActiveURLObserver(
-    HandoffActiveURLObserverDelegate* delegate)
-    : delegate_(delegate),
-      active_tab_strip_model_(nullptr),
-      active_browser_(nullptr) {
-  DCHECK(delegate_);
-
-  active_browser_ = chrome::FindLastActiveWithHostDesktopType(
-      chrome::HOST_DESKTOP_TYPE_NATIVE);
-  BrowserList::AddObserver(this);
-  UpdateObservations();
-}
-
-HandoffActiveURLObserver::~HandoffActiveURLObserver() {
-  BrowserList::RemoveObserver(this);
-  StopObservingTabStripModel();
-  StopObservingWebContents();
-}
-
-void HandoffActiveURLObserver::OnBrowserSetLastActive(Browser* browser) {
-  active_browser_ = browser;
-  UpdateObservations();
-  delegate_->HandoffActiveURLChanged(GetActiveWebContents());
-}
-
-void HandoffActiveURLObserver::OnBrowserRemoved(Browser* removed_browser) {
-  if (active_browser_ != removed_browser)
-    return;
-
-  active_browser_ = chrome::FindLastActiveWithHostDesktopType(
-      chrome::HOST_DESKTOP_TYPE_NATIVE);
-  UpdateObservations();
-  delegate_->HandoffActiveURLChanged(GetActiveWebContents());
-}
-
-void HandoffActiveURLObserver::ActiveTabChanged(
-    content::WebContents* old_contents,
-    content::WebContents* new_contents,
-    int index,
-    int reason) {
-  StartObservingWebContents(new_contents);
-  delegate_->HandoffActiveURLChanged(new_contents);
-}
-
-void HandoffActiveURLObserver::TabStripModelDeleted() {
-  StopObservingTabStripModel();
-  StopObservingWebContents();
-}
-
-void HandoffActiveURLObserver::DidNavigateMainFrame(
-    const content::LoadCommittedDetails& details,
-    const content::FrameNavigateParams& params) {
-  delegate_->HandoffActiveURLChanged(web_contents());
-}
-
-void HandoffActiveURLObserver::WebContentsDestroyed() {
-  StopObservingWebContents();
-}
-
-void HandoffActiveURLObserver::UpdateObservations() {
-  if (!active_browser_) {
-    StopObservingTabStripModel();
-    StopObservingWebContents();
-    return;
-  }
-
-  TabStripModel* model = active_browser_->tab_strip_model();
-  StartObservingTabStripModel(model);
-
-  content::WebContents* web_contents = model->GetActiveWebContents();
-  if (web_contents)
-    StartObservingWebContents(web_contents);
-  else
-    StopObservingWebContents();
-}
-
-void HandoffActiveURLObserver::StartObservingTabStripModel(
-    TabStripModel* tab_strip_model) {
-  DCHECK(tab_strip_model);
-
-  if (active_tab_strip_model_ == tab_strip_model)
-    return;
-
-  StopObservingTabStripModel();
-  tab_strip_model->AddObserver(this);
-  active_tab_strip_model_ = tab_strip_model;
-}
-
-void HandoffActiveURLObserver::StopObservingTabStripModel() {
-  if (active_tab_strip_model_) {
-    active_tab_strip_model_->RemoveObserver(this);
-    active_tab_strip_model_ = nullptr;
-  }
-}
-
-void HandoffActiveURLObserver::StartObservingWebContents(
-    content::WebContents* web_contents) {
-  DCHECK(web_contents);
-  Observe(web_contents);
-}
-
-void HandoffActiveURLObserver::StopObservingWebContents() {
-  Observe(nullptr);
-}
-
-content::WebContents* HandoffActiveURLObserver::GetActiveWebContents() {
-  if (!active_browser_)
-    return nullptr;
-
-  return active_browser_->tab_strip_model()->GetActiveWebContents();
-}