PepperOutputProtectionMessageFilter: set window_ only when client_id_ is valid.

chrome/browser/chromeos/display/output_protection_delegate.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 "chrome/browser/chromeos/display/output_protection_delegate.h"
 
 #include "ash/shell.h"
 #include "ash/shell_delegate.h"
 #include "build/build_config.h"
 #include "chrome/browser/media/media_capture_devices_dispatcher.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/render_frame_host.h"
 #include "content/public/browser/web_contents.h"
 #include "ui/gfx/screen.h"
 
 namespace chromeos {
 
 namespace {
 
 bool GetCurrentDisplayId(content::RenderFrameHost* rfh, int64* display_id) {
   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
+  DCHECK(rfh);
+  DCHECK(display_id);
+
   gfx::NativeView native_view = rfh->GetNativeView();
   gfx::Screen* screen = gfx::Screen::GetScreenFor(native_view);
   if (!screen)
     return false;
   gfx::Display display = screen->GetDisplayNearestWindow(native_view);
   *display_id = display.id();
   return true;
 }
 
 void DoNothing(bool status) {
@@ skipping 22 matching lines @@
   if (window_)
     window_->RemoveObserver(this);
 }
 
 ui::DisplayConfigurator::ContentProtectionClientId
 OutputProtectionDelegate::GetClientId() {
   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
   if (client_id_ == ui::DisplayConfigurator::kInvalidClientId) {
     content::RenderFrameHost* rfh =
         content::RenderFrameHost::FromID(render_process_id_, render_frame_id_);
-    if (!GetCurrentDisplayId(rfh, &display_id_))
+    if (!rfh || !GetCurrentDisplayId(rfh, &display_id_))
       return ui::DisplayConfigurator::kInvalidClientId;
 
-    window_ = rfh->GetNativeView();
-    if (!window_)
+    aura::Window* window = rfh->GetNativeView();
+    if (!window)
       return ui::DisplayConfigurator::kInvalidClientId;
 
     ui::DisplayConfigurator* configurator =
         ash::Shell::GetInstance()->display_configurator();
     client_id_ = configurator->RegisterContentProtectionClient();
 
-    if (client_id_ != ui::DisplayConfigurator::kInvalidClientId)
-      window_->AddObserver(this);
+    if (client_id_ != ui::DisplayConfigurator::kInvalidClientId) {
+      window->AddObserver(this);
+      window_ = window;
+    }
   }
   return client_id_;
 }
 
 void OutputProtectionDelegate::QueryStatus(
     const QueryStatusCallback& callback) {
   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
 
   content::RenderFrameHost* rfh =
       content::RenderFrameHost::FromID(render_process_id_, render_frame_id_);
@@ skipping 92 matching lines @@
   display_id_ = new_display_id;
 }
 
 void OutputProtectionDelegate::OnWindowDestroying(aura::Window* window) {
   DCHECK_EQ(window, window_);
   window_->RemoveObserver(this);
   window_ = nullptr;
 }
 
 }  // namespace chromeos