Current work-in-progress crbug.com/567021

third_party/WebKit/Source/core/css/resolver/ViewportStyleResolver.cpp

Index: third_party/WebKit/Source/core/css/resolver/ViewportStyleResolver.cpp
diff --git a/third_party/WebKit/Source/core/css/resolver/ViewportStyleResolver.cpp b/third_party/WebKit/Source/core/css/resolver/ViewportStyleResolver.cpp
index 1e40fcd4343b4d4246ffeb2f9f95faae56b42af8..f9c1ee77e06f765b819976b2fc127a9221cea67e 100644
--- a/third_party/WebKit/Source/core/css/resolver/ViewportStyleResolver.cpp
+++ b/third_party/WebKit/Source/core/css/resolver/ViewportStyleResolver.cpp
@@ -32,10 +32,11 @@
 #include "core/CSSValueKeywords.h"
 #include "core/css/CSSDefaultStyleSheets.h"
 #include "core/css/CSSPrimitiveValueMappings.h"
+#include "core/css/CSSStyleSheet.h"
 #include "core/css/CSSToLengthConversionData.h"
 #include "core/css/StylePropertySet.h"
 #include "core/css/StyleRule.h"
-#include "core/css/resolver/ScopedStyleResolver.h"
+#include "core/css/StyleSheetContents.h"
 #include "core/dom/Document.h"
 #include "core/dom/NodeComputedStyle.h"
 #include "core/dom/ViewportDescription.h"
@@ -45,52 +46,68 @@ namespace blink {
 
 ViewportStyleResolver::ViewportStyleResolver(Document* document)
     : m_document(document)
-    , m_hasAuthorStyle(false)
 {
     ASSERT(m_document);
+    m_initialViewportMedium = new MediaQueryEvaluator(document->frame());
 }
 
-void ViewportStyleResolver::collectViewportRules()
+void ViewportStyleResolver::reset()
+{
+    m_viewportDependentMediaQueryResults.clear();
+    m_deviceDependentMediaQueryResults.clear();
+    m_propertySet = nullptr;
+    m_hasAuthorStyle = false;
+}
+
+void ViewportStyleResolver::collectViewportRulesFromUASheets()
 {
     CSSDefaultStyleSheets& defaultStyleSheets = CSSDefaultStyleSheets::instance();
-    collectViewportRules(defaultStyleSheets.defaultStyle(), UserAgentOrigin);
 
     WebViewportStyle viewportStyle = m_document->settings() ? m_document->settings()->viewportStyle() : WebViewportStyle::Default;
-    RuleSet* viewportRules = nullptr;
+    StyleSheetContents* viewportContents = nullptr;
     switch (viewportStyle) {
     case WebViewportStyle::Default:
         break;
     case WebViewportStyle::Mobile:
-        viewportRules = defaultStyleSheets.defaultMobileViewportStyle();
+        viewportContents = defaultStyleSheets.ensureMobileViewportStyleSheet();
         break;
     case WebViewportStyle::Television:
-        viewportRules = defaultStyleSheets.defaultTelevisionViewportStyle();
+        viewportContents = defaultStyleSheets.ensureTelevisionViewportStyleSheet();
         break;
     }
-    if (viewportRules)
-        collectViewportRules(viewportRules, UserAgentOrigin);
-
+    if (viewportContents)
+        collectViewportChildRules(viewportContents->childRules(), UserAgentOrigin);
     if (m_document->isMobileDocument())
-        collectViewportRules(defaultStyleSheets.defaultXHTMLMobileProfileStyle(), UserAgentOrigin);
+        collectViewportChildRules(defaultStyleSheets.ensureXHTMLMobileProfileStyleSheet()->childRules(), UserAgentOrigin);
+}
+
+void ViewportStyleResolver::collectViewportRulesFromAuthorSheet(const CSSStyleSheet& sheet)
+{
+    if (!sheet.contents()->hasViewportRule())
+        return;
 
-    if (ScopedStyleResolver* scopedResolver = m_document->scopedStyleResolver())
-        scopedResolver->collectViewportRulesTo(this);
+    if (sheet.mediaQueries() && !m_initialViewportMedium->eval(sheet.mediaQueries(), &m_viewportDependentMediaQueryResults, &m_deviceDependentMediaQueryResults))
+        return;
 
-    resolve();
+    collectViewportChildRules(sheet.contents()->childRules(), AuthorOrigin);
 }
 
-void ViewportStyleResolver::collectViewportRules(RuleSet* rules, Origin origin)
+void ViewportStyleResolver::collectViewportChildRules(const HeapVector<Member<StyleRuleBase>>& rules, Origin origin)
 {
-    rules->compactRulesIfNeeded();
-
-    const HeapVector<Member<StyleRuleViewport>>& viewportRules = rules->viewportRules();
-    for (size_t i = 0; i < viewportRules.size(); ++i)
-        addViewportRule(viewportRules[i], origin);
+    for (auto& rule : rules) {
+        if (rule->isViewportRule())
+            addViewportRule(*toStyleRuleViewport(rule), origin);
+        if (!rule->isMediaRule())
+            continue;
+        StyleRuleMedia* mediaRule = toStyleRuleMedia(rule);
+        if (!mediaRule->mediaQueries() || m_initialViewportMedium->eval(mediaRule->mediaQueries(), &m_viewportDependentMediaQueryResults, &m_deviceDependentMediaQueryResults))
+            collectViewportChildRules(mediaRule->childRules(), origin);
+    }
 }
 
-void ViewportStyleResolver::addViewportRule(StyleRuleViewport* viewportRule, Origin origin)
+void ViewportStyleResolver::addViewportRule(StyleRuleViewport& viewportRule, Origin origin)
 {
-    StylePropertySet& propertySet = viewportRule->mutableProperties();
+    StylePropertySet& propertySet = viewportRule.mutableProperties();
 
     unsigned propertyCount = propertySet.propertyCount();
     if (!propertyCount)
@@ -130,9 +147,6 @@ void ViewportStyleResolver::resolve()
     description.orientation = viewportArgumentValue(CSSPropertyOrientation);
 
     m_document->setViewportDescription(description);
-
-    m_propertySet = nullptr;
-    m_hasAuthorStyle = false;
 }
 
 float ViewportStyleResolver::viewportArgumentValue(CSSPropertyID id) const
@@ -226,8 +240,11 @@ Length ViewportStyleResolver::viewportLengthValue(CSSPropertyID id) const
 
 DEFINE_TRACE(ViewportStyleResolver)
 {
-    visitor->trace(m_propertySet);
     visitor->trace(m_document);
+    visitor->trace(m_propertySet);
+    visitor->trace(m_initialViewportMedium);
+    visitor->trace(m_viewportDependentMediaQueryResults);
+    visitor->trace(m_deviceDependentMediaQueryResults);
 }
 
 } // namespace blink