Defer loads in new pages/frames if ScopedPageLoadDeferral is active

third_party/WebKit/Source/core/page/ScopedPageLoadDeferrer.cpp

 /*
  * Copyright (C) 2006, 2007, 2009 Apple Inc. All rights reserved.
  * Copyright (C) 2008 Nokia Corporation and/or its subsidiary(-ies)
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Library General Public License for more details.
  *
  * You should have received a copy of the GNU Library General Public License
  * along with this library; see the file COPYING.LIB.  If not, write to
  * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  * Boston, MA 02110-1301, USA.
  */
 
 #include "core/page/ScopedPageLoadDeferrer.h"
 
 #include "core/dom/Document.h"
-#include "core/frame/LocalFrame.h"
 #include "core/loader/FrameLoader.h"
 #include "core/page/Page.h"
+#include "platform/heap/Handle.h"
 #include "public/platform/Platform.h"
 #include "public/platform/WebScheduler.h"
-#include "wtf/HashSet.h"
+#include "wtf/StdLibExtras.h"
+#include "wtf/Vector.h"
 
 namespace blink {
 
-ScopedPageLoadDeferrer::ScopedPageLoadDeferrer(Page* exclusion)
+namespace {
+
+using DeferredPages = Vector<Persistent<Page>, 16>;
+
+unsigned s_deferralCount = 0;
+
+DeferredPages& deferredPages()
 {
+    DEFINE_STATIC_LOCAL(DeferredPages, pages, ());
+    return pages;
+}
+
+void setDefersLoading(bool isDeferred)
+{
+    for (const auto& page : deferredPages())
+        page->setDefersLoading(isDeferred);
+}
+
+} // namespace
+
+ScopedPageLoadDeferrer::ScopedPageLoadDeferrer()
+{
+    if (++s_deferralCount > 1)
+        return;
+
     for (Page* page : Page::ordinaryPages()) {
-        if (page == exclusion || page->defersLoading())
+        if (page->defersLoading())
             continue;
-        m_deferredPages.append(page);
+        deferredPages().append(page);
     }
 
     setDefersLoading(true);
     Platform::current()->currentThread()->scheduler()->suspendTimerQueue();
 }
 
 ScopedPageLoadDeferrer::~ScopedPageLoadDeferrer()
 {
-    setDefersLoading(false);
-    Platform::current()->currentThread()->scheduler()->resumeTimerQueue();
+    if (--s_deferralCount == 0) {
+        setDefersLoading(false);
+        Platform::current()->currentThread()->scheduler()->resumeTimerQueue();
+    }
 }
 
-void ScopedPageLoadDeferrer::setDefersLoading(bool isDeferred)
+void ScopedPageLoadDeferrer::deferIfNeeded(Page* page)
 {
-
-    for (const auto& page : m_deferredPages)
-        page->setDefersLoading(isDeferred);
+    if (s_deferralCount > 0) {
+        deferredPages().append(page);
+        page->setDefersLoading(true);
+    }
 }
 
 } // namespace blink