Have srcset respond to viewport changes

Source/core/dom/Document.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  *           (C) 2006 Alexey Proskuryakov (ap@webkit.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2011, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  * Copyright (C) 2008, 2009, 2011, 2012 Google Inc. All rights reserved.
  * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies)
  * Copyright (C) Research In Motion Limited 2010-2011. All rights reserved.
@@ skipping 97 matching lines @@
 #include "core/events/PageTransitionEvent.h"
 #include "core/events/ScopedEventQueue.h"
 #include "core/fetch/ResourceFetcher.h"
 #include "core/frame/LocalDOMWindow.h"
 #include "core/frame/FrameConsole.h"
 #include "core/frame/FrameHost.h"
 #include "core/frame/FrameView.h"
 #include "core/frame/History.h"
 #include "core/frame/LocalFrame.h"
 #include "core/frame/Settings.h"
+#include "core/frame/ViewportChangeNotifier.h"
 #include "core/frame/csp/ContentSecurityPolicy.h"
 #include "core/html/DocumentNameCollection.h"
 #include "core/html/HTMLAllCollection.h"
 #include "core/html/HTMLAnchorElement.h"
 #include "core/html/HTMLBaseElement.h"
 #include "core/html/HTMLCanvasElement.h"
 #include "core/html/HTMLCollection.h"
 #include "core/html/HTMLDialogElement.h"
 #include "core/html/HTMLDocument.h"
 #include "core/html/HTMLFrameOwnerElement.h"
@@ skipping 357 matching lines @@
 #endif
     , m_contextDocument(initializer.contextDocument())
     , m_hasFullscreenElementStack(false)
     , m_loadEventDelayCount(0)
     , m_loadEventDelayTimer(this, &Document::loadEventDelayTimerFired)
     , m_pluginLoadingTimer(this, &Document::pluginLoadingTimerFired)
     , m_didSetReferrerPolicy(false)
     , m_referrerPolicy(ReferrerPolicyDefault)
     , m_directionSetOnDocumentElement(false)
     , m_writingModeSetOnDocumentElement(false)
+    , m_viewportChangeNotifier(ViewportChangeNotifier::create())
     , m_writeRecursionIsTooDeep(false)
     , m_writeRecursionDepth(0)
     , m_taskRunner(MainThreadTaskRunner::create(this))
     , m_registrationContext(initializer.registrationContext(this))
     , m_elementDataCacheClearTimer(this, &Document::elementDataCacheClearTimerFired)
 #ifndef NDEBUG
     , m_didDispatchViewportPropertiesChanged(false)
 #endif
     , m_timeline(AnimationTimeline::create(this))
     , m_templateDocumentHost(nullptr)
@@ skipping 2880 matching lines @@
     if (!m_evaluateMediaQueriesOnStyleRecalc)
         return;
     evaluateMediaQueryList();
     m_evaluateMediaQueriesOnStyleRecalc = false;
 }
 
 void Document::evaluateMediaQueryList()
 {
     if (m_mediaQueryMatcher)
         m_mediaQueryMatcher->mediaFeaturesChanged();
+    m_viewportChangeNotifier->viewportChanged();

[esprehn, 2014/07/14 08:39:49]

This is synchronous, which is specifically what I didn't want and why Christian
made the listeners fire at raf time.

 }
 
 void Document::notifyResizeForViewportUnits()
 {
     if (!hasViewportUnits())
         return;
     ensureStyleResolver().notifyResizeForViewportUnits();
     setNeedsStyleRecalcForViewportUnits();
 }
 
@@ skipping 2357 matching lines @@
 using namespace WebCore;
 void showLiveDocumentInstances()
 {
     WeakDocumentSet& set = liveDocumentSet();
     fprintf(stderr, "There are %u documents currently alive:\n", set.size());
     for (WeakDocumentSet::const_iterator it = set.begin(); it != set.end(); ++it) {
         fprintf(stderr, "- Document %p URL: %s\n", *it, (*it)->url().string().utf8().data());
     }
 }
 #endif