Move viewport unit resolution to style recalc time

Source/core/dom/ViewportDescription.cpp

Index: Source/core/dom/ViewportDescription.cpp
diff --git a/Source/core/dom/ViewportDescription.cpp b/Source/core/dom/ViewportDescription.cpp
index 77f924e623ba812de4200e337901fd69f67722f3..0c5b1d5cbdbb674dd97036ec284fb36d818f8a9d 100644
--- a/Source/core/dom/ViewportDescription.cpp
+++ b/Source/core/dom/ViewportDescription.cpp
@@ -54,17 +54,17 @@ float ViewportDescription::resolveViewportLength(const Length& length, const Flo
     if (length.type() == ExtendToZoom)
         return ViewportDescription::ValueExtendToZoom;
 
-    if ((length.type() == Percent && direction == Horizontal) || length.type() == ViewportPercentageWidth)
-        return initialViewportSize.width() * length.getFloatValue() / 100.0f;
-
-    if ((length.type() == Percent && direction == Vertical) || length.type() == ViewportPercentageHeight)
-        return initialViewportSize.height() * length.getFloatValue() / 100.0f;
-
-    if (length.type() == ViewportPercentageMin)
-        return min(initialViewportSize.width(), initialViewportSize.height()) * length.viewportPercentageLength() / 100.0f;
-
-    if (length.type() == ViewportPercentageMax)
-        return max(initialViewportSize.width(), initialViewportSize.height()) * length.viewportPercentageLength() / 100.0f;
+    if (length.type() == Percent) {
+        float value = length.getFloatValue();
+        if (value >= 0 && direction == Horizontal)
+            return initialViewportSize.width() * length.getFloatValue() / 100.0f;
+        if (value >= 0 && direction == Vertical)
+            return initialViewportSize.height() * length.getFloatValue() / 100.0f;
+        if (value == -1)
+            return initialViewportSize.width();
+        if (value == -2)
+            return initialViewportSize.height();
+    }
 
     ASSERT_NOT_REACHED();
     return ViewportDescription::ValueAuto;