Use css-device-adapt constraining for legacy viewport tags.

Source/core/css/resolver/ViewportStyleResolver.cpp

 /*
  * Copyright (C) 2012-2013 Intel Corporation. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1. Redistributions of source code must retain the above
  *    copyright notice, this list of conditions and the following
  *    disclaimer.
@@ skipping 22 matching lines @@
 #include "CSSValueKeywords.h"
 #include "core/css/StylePropertySet.h"
 #include "core/css/StyleRule.h"
 #include "core/dom/Document.h"
 #include "core/dom/NodeRenderStyle.h"
 #include "core/dom/ViewportArguments.h"
 
 namespace WebCore {
 
 ViewportStyleResolver::ViewportStyleResolver(Document* document)
-    : m_document(document)
+    : m_document(document),
+    m_hasAuthorStyle(false)
 {
     ASSERT(m_document);
 }
 
 ViewportStyleResolver::~ViewportStyleResolver()
 {
 }
 
 void ViewportStyleResolver::addViewportRule(StyleRuleViewport* viewportRule)
 {
@@ skipping 17 matching lines @@
 void ViewportStyleResolver::clearDocument()
 {
     m_document = 0;
 }
 
 void ViewportStyleResolver::resolve()
 {
     if (!m_document)
         return;
 
-    if (!m_propertySet) {
-        // FIXME: This is not entirely correct. If the doctype is XHTML MP, or there is a Meta
-        // element for setting the viewport, the viewport arguments should fall back to those
-        // settings when the @viewport rules are all removed. For now, reset to implicit when
-        // there was an @viewport rule which has now been removed.
-        if (m_document->viewportArguments().type == ViewportArguments::CSSDeviceAdaptation) {
+    if (!m_hasAuthorStyle && (m_document->useLegacyViewportArguments() || !m_propertySet)) {
+        if (!m_propertySet)
             m_document->setViewportArguments(ViewportArguments());
-            m_document->updateViewportArguments();
-        }
+        else
+            m_propertySet = 0;
         return;
     }
 
-    ViewportArguments arguments(ViewportArguments::CSSDeviceAdaptation);
+    ASSERT(m_propertySet);
+
+    ViewportArguments arguments(m_hasAuthorStyle ? ViewportArguments::AuthorStyleSheet : ViewportArguments::UserAgentStyleSheet);
 
     arguments.userZoom = getViewportArgumentValue(CSSPropertyUserZoom);
     arguments.zoom = getViewportArgumentValue(CSSPropertyZoom);
     arguments.minZoom = getViewportArgumentValue(CSSPropertyMinZoom);
     arguments.maxZoom = getViewportArgumentValue(CSSPropertyMaxZoom);
     arguments.minWidth = getViewportArgumentValue(CSSPropertyMinWidth);
     arguments.maxWidth = getViewportArgumentValue(CSSPropertyMaxWidth);
     arguments.minHeight = getViewportArgumentValue(CSSPropertyMinHeight);
     arguments.maxHeight = getViewportArgumentValue(CSSPropertyMaxHeight);
     arguments.orientation = getViewportArgumentValue(CSSPropertyOrientation);
 
     m_document->setViewportArguments(arguments);
-    m_document->updateViewportArguments();
 
     m_propertySet = 0;
+    m_hasAuthorStyle = false;
 }
 
 float ViewportStyleResolver::getViewportArgumentValue(CSSPropertyID id) const
 {
     float defaultValue = ViewportArguments::ValueAuto;
 
     // UserZoom default value is CSSValueZoom, which maps to true, meaning that
     // yes, it is user scalable. When the value is set to CSSValueFixed, we
     // return false.
     if (id == CSSPropertyUserZoom)
@@ skipping 42 matching lines @@
     case CSSValueInternalExtendToZoom:
         return ViewportArguments::ValueExtendToZoom;
     case CSSValueFixed:
         return 0;
     default:
         return defaultValue;
     }
 }
 
 } // namespace WebCore