Move viewport unit resolution to style recalc time

Source/core/html/HTMLMetaElement-in.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2003, 2010 Apple Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
@@ skipping 152 matching lines @@
         reportViewportWarning(TruncatedViewportArgumentValueError, valueString, keyString);
     if (ok)
         *ok = true;
     return value;
 }
 
 Length HTMLMetaElement::parseViewportValueAsLength(const String& keyString, const String& valueString)
 {
     // 1) Non-negative number values are translated to px lengths.
     // 2) Negative number values are translated to auto.
-    // 3) device-width and device-height are used as keywords.
+    // FIXME: We shouldn't abuse Lengths like this
+    // 3) device-width and device-height are translated to -1% and -2%

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

Woah.

     // 4) Other keywords and unknown values translate to 0.0.
 
     unsigned length = valueString.length();
     DEFINE_ARRAY_FOR_MATCHING(characters, valueString, 13);
     SWITCH(characters, length) {
         CASE("device-width") {
-            return Length(100, ViewportPercentageWidth);
+            return Length(-1, Percent);
         }
         CASE("device-height") {
-            return Length(100, ViewportPercentageHeight);
+            return Length(-2, Percent);
         }
     }
 
     float value = parsePositiveNumber(keyString, valueString);
 
     if (value < 0)
         return Length(); // auto
 
     return Length(clampLengthValue(value), Fixed);
 }
@@ skipping 286 matching lines @@
 {
     return getAttribute(http_equivAttr);
 }
 
 String HTMLMetaElement::name() const
 {
     return getNameAttribute();
 }
 
 }