Move viewport unit resolution to style recalc time

Source/core/html/HTMLMetaElement-in.cpp

Index: Source/core/html/HTMLMetaElement-in.cpp
diff --git a/Source/core/html/HTMLMetaElement-in.cpp b/Source/core/html/HTMLMetaElement-in.cpp
index 18697f4b4420fde18c11de22f4ee156c04c45e7b..e456bea425dd05e6af8ced75937a4fede8b494d8 100644
--- a/Source/core/html/HTMLMetaElement-in.cpp
+++ b/Source/core/html/HTMLMetaElement-in.cpp
@@ -170,17 +170,18 @@ Length HTMLMetaElement::parseViewportValueAsLength(const String& keyString, cons
 {
     // 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%
     // 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);
         }
     }