Change CaptureSynchronizer and PointerWatcherEventRouter to support multiple CaptureClients.

ui/views/widget/desktop_aura/desktop_capture_client.cc

 // Copyright 2013 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 "ui/views/widget/desktop_aura/desktop_capture_client.h"
 
+#include "ui/aura/client/capture_client_observer.h"
 #include "ui/aura/window.h"
 #include "ui/aura/window_event_dispatcher.h"
 #include "ui/aura/window_tracker.h"
 #include "ui/aura/window_tree_host.h"
 
 namespace views {
 
 // static
 DesktopCaptureClient::CaptureClients* DesktopCaptureClient::capture_clients_ =
     nullptr;
@@ skipping 61 matching lines @@
     CaptureClients capture_clients(*capture_clients_);
     for (CaptureClients::iterator i = capture_clients.begin();
          i != capture_clients.end(); ++i) {
       if (*i != this) {
         aura::client::CaptureDelegate* delegate =
             (*i)->root_->GetHost()->dispatcher();
         delegate->OnOtherRootGotCapture();
       }
     }
   }  // else case is capture is remaining in our root, nothing to do.
+
+  for (aura::client::CaptureClientObserver& observer : observers_)

[sadrul, 2017/01/27 01:06:54]

for (auto& observer : observers_)

[riajiang, 2017/01/30 18:36:22]

Done.

+    observer.OnCaptureChanged(old_capture_window, capture_window_);
 }
 
 void DesktopCaptureClient::ReleaseCapture(aura::Window* window) {
   if (capture_window_ != window)
     return;
   SetCapture(nullptr);
 }
 
 aura::Window* DesktopCaptureClient::GetCaptureWindow() {
   return capture_window_;
 }
 
 aura::Window* DesktopCaptureClient::GetGlobalCaptureWindow() {
   return GetCaptureWindowGlobal();
 }
 
 void DesktopCaptureClient::AddObserver(
     aura::client::CaptureClientObserver* observer) {
-  NOTREACHED();
+  observers_.AddObserver(observer);
 }
 
 void DesktopCaptureClient::RemoveObserver(
     aura::client::CaptureClientObserver* observer) {
-  NOTREACHED();
+  observers_.RemoveObserver(observer);
 }
 
 }  // namespace views