Move viewport unit resolution to style recalc time

Source/web/WebViewImpl.cpp

 /*
  * Copyright (C) 2011, 2012 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 2969 matching lines @@
 {
     if (!settings()->viewportEnabled() || !page() || !m_size.width || !m_size.height)
         return;
 
     ViewportDescription adjustedDescription = description;
     if (settingsImpl()->viewportMetaLayoutSizeQuirk() && adjustedDescription.type == ViewportDescription::ViewportMeta) {
         if (adjustedDescription.maxWidth.type() == ExtendToZoom)
             adjustedDescription.maxWidth = Length(); // auto
         const int legacyWidthSnappingMagicNumber = 320;
         if (adjustedDescription.maxWidth.isFixed() && adjustedDescription.maxWidth.value() <= legacyWidthSnappingMagicNumber)
-            adjustedDescription.maxWidth = Length(100, ViewportPercentageWidth);
+            adjustedDescription.maxWidth = Length(-1, Percent);
         if (adjustedDescription.maxHeight.isFixed() && adjustedDescription.maxWidth.value() <= m_size.height)
-            adjustedDescription.maxHeight = Length(100, ViewportPercentageHeight);
+            adjustedDescription.maxHeight = Length(-2, Percent);

[esprehn, 2013/12/04 06:02:28]

This makes me nervous... why the magic lengths?

         adjustedDescription.minWidth = adjustedDescription.maxWidth;
         adjustedDescription.minHeight = adjustedDescription.maxHeight;
     }
     float oldInitialScale = m_pageScaleConstraintsSet.pageDefinedConstraints().initialScale;
     m_pageScaleConstraintsSet.updatePageDefinedConstraints(adjustedDescription, m_size);
 
     if (settingsImpl()->clobberUserAgentInitialScaleQuirk()
         && m_pageScaleConstraintsSet.userAgentConstraints().initialScale != -1
         && m_pageScaleConstraintsSet.userAgentConstraints().initialScale * deviceScaleFactor() <= 1) {
-        if (description.maxWidth == Length(100, ViewportPercentageWidth)
+        if (description.maxWidth == Length(-1, Percent)
             || (description.maxWidth.type() == ExtendToZoom && m_pageScaleConstraintsSet.pageDefinedConstraints().initialScale == 1.0f))
             setInitialPageScaleOverride(-1);
     }
     m_pageScaleConstraintsSet.adjustForAndroidWebViewQuirks(adjustedDescription, m_size, page()->settings().layoutFallbackWidth(), deviceScaleFactor(), settingsImpl()->supportDeprecatedTargetDensityDPI(), page()->settings().wideViewportQuirkEnabled(), page()->settings().useWideViewport(), page()->settings().loadWithOverviewMode(), settingsImpl()->viewportMetaNonUserScalableQuirk());
     float newInitialScale = m_pageScaleConstraintsSet.pageDefinedConstraints().initialScale;
     if (oldInitialScale != newInitialScale && newInitialScale != -1) {
         m_pageScaleConstraintsSet.setNeedsReset(true);
         if (mainFrameImpl() && mainFrameImpl()->frameView())
             mainFrameImpl()->frameView()->setNeedsLayout();
     }
@@ skipping 1162 matching lines @@
     const PageScaleConstraints& constraints = m_pageScaleConstraintsSet.pageDefinedConstraints();
 
     if (!mainFrameImpl() || !mainFrameImpl()->frameView())
         return false;
 
     return mainFrameImpl()->frameView()->layoutSize().width() == m_size.width
         || (constraints.minimumScale == constraints.maximumScale && constraints.minimumScale != -1);
 }
 
 } // namespace blink