Translate viewport related meta tags into @viewport descriptors as suggested by the CSS Device Adap…

Source/core/css/resolver/StyleResolver.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 2004-2005 Allan Sandfeld Jensen (kde@carewolf.com)
  * Copyright (C) 2006, 2007 Nicholas Shanks (webkit@nickshanks.com)
  * Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013 Apple Inc. All rights reserved.
  * Copyright (C) 2007 Alexey Proskuryakov <ap@webkit.org>
  * Copyright (C) 2007, 2008 Eric Seidel <eric@webkit.org>
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  * Copyright (c) 2011, Code Aurora Forum. All rights reserved.
  * Copyright (C) Research In Motion Limited 2011. All rights reserved.
@@ skipping 35 matching lines @@
 #include "core/css/CSSKeyframesRule.h"
 #include "core/css/CSSLineBoxContainValue.h"
 #include "core/css/CSSParser.h"
 #include "core/css/CSSPrimitiveValueMappings.h"
 #include "core/css/CSSReflectValue.h"
 #include "core/css/CSSSVGDocumentValue.h"
 #include "core/css/CSSSelector.h"
 #include "core/css/CSSSelectorList.h"
 #include "core/css/CSSStyleRule.h"
 #include "core/css/CSSValueList.h"
+#include "core/css/CSSValuePool.h"
 #include "core/css/CSSVariableValue.h"
 #include "core/css/ElementRuleCollector.h"
 #include "core/css/FontFeatureValue.h"
 #include "core/css/FontSize.h"
 #include "core/css/MediaQueryEvaluator.h"
 #include "core/css/PageRuleCollector.h"
 #include "core/css/Pair.h"
 #include "core/css/RuleSet.h"
 #include "core/css/StylePropertySet.h"
 #include "core/css/StylePropertyShorthand.h"
@@ skipping 14 matching lines @@
 #include "core/dom/WebCoreMemoryInstrumentation.h"
 #include "core/dom/shadow/ShadowRoot.h"
 #include "core/html/HTMLHtmlElement.h"
 #include "core/html/HTMLIFrameElement.h"
 #include "core/inspector/InspectorInstrumentation.h"
 #include "core/loader/cache/CachedDocument.h"
 #include "core/loader/cache/CachedSVGDocumentReference.h"
 #include "core/page/Frame.h"
 #include "core/page/FrameView.h"
 #include "core/page/Page.h"
+#include "core/page/PageGroup.h"
 #include "core/page/Settings.h"
+#include "core/page/UserStyleSheet.h"
 #include "core/platform/graphics/filters/custom/CustomFilterConstants.h"
 #include "core/platform/text/LocaleToScriptMapping.h"
 #include "core/rendering/RenderView.h"
 #include "core/rendering/style/KeyframeList.h"
 #include "core/rendering/style/StyleCustomFilterProgramCache.h"
 #include "core/svg/SVGDocumentExtensions.h"
 #include "core/svg/SVGElement.h"
 #include "core/svg/SVGFontFaceElement.h"
 #include "wtf/MemoryInstrumentationHashMap.h"
 #include "wtf/MemoryInstrumentationVector.h"
@@ skipping 56 matching lines @@
         m_medium = adoptPtr(new MediaQueryEvaluator("all"));
 
     if (root)
         m_rootDefaultStyle = styleForElement(root, 0, DisallowStyleSharing, MatchOnlyUserAgentRules);
 
     if (m_rootDefaultStyle && view)
         m_medium = adoptPtr(new MediaQueryEvaluator(view->mediaType(), view->frame(), m_rootDefaultStyle.get()));
 
     m_styleTree.clear();
 
+    if (document->isXHTMLMobileProfile()) {
+        Vector<String> whitelist;
+        whitelist.append(document->url());
+        static const char* sheet = "@viewport{-internal-priority:1;width:auto;height:auto;zoom:1;}";
+        document->page()->group().addUserStyleSheet(sheet, KURL(), whitelist, Vector<String>(), InjectInAllFrames, UserStyleAuthorLevel, InjectInExistingDocuments);
+    }
+
     DocumentStyleSheetCollection* styleSheetCollection = document->styleSheetCollection();
     m_ruleSets.initUserStyle(styleSheetCollection, *m_medium, *this);
 
 #if ENABLE(SVG_FONTS)
     if (document->svgExtensions()) {
         const HashSet<SVGFontFaceElement*>& svgFontFaceElements = document->svgExtensions()->svgFontFaceElements();
         HashSet<SVGFontFaceElement*>::const_iterator end = svgFontFaceElements.end();
         for (HashSet<SVGFontFaceElement*>::const_iterator it = svgFontFaceElements.begin(); it != end; ++it)
             fontSelector()->addFontFaceRule((*it)->fontFaceRule());
     }
 #endif
 
     // FIXME: Stylesheet candidate nodes are sorted in document order, but scoping nodes are not sorted.
     appendAuthorStyleSheets(0, styleSheetCollection->activeAuthorStyleSheets());
 }
 
 void StyleResolver::appendAuthorStyleSheets(unsigned firstNew, const Vector<RefPtr<CSSStyleSheet> >& styleSheets)
 {
     // This handles sheets added to the end of the stylesheet list only. In other cases the style resolver
     // needs to be reconstructed. To handle insertions too the rule order numbers would need to be updated.
     unsigned size = styleSheets.size();
     for (unsigned i = firstNew; i < size; ++i) {
         CSSStyleSheet* cssSheet = styleSheets[i].get();
+
         ASSERT(!cssSheet->disabled());
         if (cssSheet->mediaQueries() && !m_medium->eval(cssSheet->mediaQueries(), this))
             continue;
 
         StyleSheetContents* sheet = cssSheet->contents();
         ScopedStyleResolver* resolver = ensureScopedStyleResolver(ScopedStyleResolver::scopingNodeFor(cssSheet));
         ASSERT(resolver);
         resolver->addRulesFromSheet(sheet, *m_medium, this);
         m_inspectorCSSOMWrappers.collectFromStyleSheetIfNeeded(cssSheet);
     }
 
     collectFeatures();
 
     if (document()->renderer() && document()->renderer()->style())
         document()->renderer()->style()->font().update(fontSelector());
 
-    if (RuntimeEnabledFeatures::cssViewportEnabled())
-        collectViewportRules();
+    collectViewportRules();
 }
 
 void StyleResolver::resetAuthorStyle()
 {
     m_styleTree.clear();
 }
 
 void StyleResolver::resetAuthorStyle(const ContainerNode* scopingNode)
 {
     m_styleTree.clear();
@@ skipping 709 matching lines @@
     m_styleResourceLoader.loadPendingResources(state.style(), state.elementStyleResources());
 
     document()->didAccessStyleResolver();
 
     // Now return the style.
     return state.takeStyle();
 }
 
 void StyleResolver::collectViewportRules()
 {
-    ASSERT(RuntimeEnabledFeatures::cssViewportEnabled());
-
     collectViewportRules(CSSDefaultStyleSheets::defaultStyle);
     if (m_ruleSets.userStyle())
         collectViewportRules(m_ruleSets.userStyle());
 
+    // OK to collect here for viewport meta etc, only the parser doesn't allow addition
+    // of @viewport with the runtime check.
     if (ScopedStyleResolver* scopedResolver = m_styleTree.scopedStyleResolverForDocument())
         scopedResolver->collectViewportRulesTo(this);
 
     viewportStyleResolver()->resolve();
 }
 
 void StyleResolver::collectViewportRules(RuleSet* rules)
 {
-    ASSERT(RuntimeEnabledFeatures::cssViewportEnabled());
-
     rules->compactRulesIfNeeded();
 
     const Vector<StyleRuleViewport*>& viewportRules = rules->viewportRules();
     for (size_t i = 0; i < viewportRules.size(); ++i)
         viewportStyleResolver()->addViewportRule(viewportRules[i]);
 }
 
 PassRefPtr<RenderStyle> StyleResolver::defaultStyleForElement()
 {
     m_state.setStyle(RenderStyle::create());
@@ skipping 514 matching lines @@
     m_viewportDependentMediaQueryResults.append(adoptPtr(new MediaQueryResult(*expr, result)));
 }
 
 bool StyleResolver::affectedByViewportChange() const
 {
     unsigned s = m_viewportDependentMediaQueryResults.size();
     for (unsigned i = 0; i < s; i++) {
         if (m_medium->eval(&m_viewportDependentMediaQueryResults[i]->m_expression) != m_viewportDependentMediaQueryResults[i]->m_result)
             return true;
     }
-    return false;
+
+    return m_viewportStyleResolver->affectedByViewportChange();

[Mikhail, 2013/07/19 12:56:21]

This is causing dead loop if having '%' values of viewport width/height
descriptors: m_viewportStyleResolver->affectedByViewportChange() always returns
true in this case -> StyleResolver::affectedByViewportChange() returns true
also.

So have the following loop:
FrameView::performPostLayoutTasks() -> Document::styleResolverChanged() ->
view()->scheduleRelayout() -> FrameView::performPostLayoutTasks().

Document::styleResolverChanged() is invoked in
FrameView::performPostLayoutTasks() on following condition:

if (m_frame->document()->styleResolver()->affectedByViewportChange())

So, one solution could be changing it to:

if (resized && m_frame->document()->styleResolver()->affectedByViewportChange())


but first we need to make sure that it would not bring regressions to orienation
media queries.

 }
 
 void StyleResolver::reportMemoryUsage(MemoryObjectInfo* memoryObjectInfo) const
 {
     MemoryClassInfo info(memoryObjectInfo, this, WebCoreMemoryTypes::CSS);
     info.addMember(m_ruleSets, "ruleSets");
     info.addMember(m_matchedPropertiesCache, "matchedPropertiesCache");
 
     info.addMember(m_medium, "medium");
     info.addMember(m_rootDefaultStyle, "rootDefaultStyle");
     info.addMember(m_document, "document");
 
     info.addMember(m_fontSelector, "fontSelector");
     info.addMember(m_viewportDependentMediaQueryResults, "viewportDependentMediaQueryResults");
     info.addMember(m_inspectorCSSOMWrappers);
 
     info.addMember(m_styleTree, "scopedStyleTree");
     info.addMember(m_state, "state");
 
     // FIXME: move this to a place where it would be called only once?
     info.addMember(CSSDefaultStyleSheets::defaultStyle, "defaultStyle");
     info.addMember(CSSDefaultStyleSheets::defaultQuirksStyle, "defaultQuirksStyle");
     info.addMember(CSSDefaultStyleSheets::defaultPrintStyle, "defaultPrintStyle");
     info.addMember(CSSDefaultStyleSheets::defaultViewSourceStyle, "defaultViewSourceStyle");
 }
 
 } // namespace WebCore