Relayout RenderObjects with viewport-percentage CSS properties when viewport size changes

Source/core/rendering/RenderObject.cpp

Index: Source/core/rendering/RenderObject.cpp
diff --git a/Source/core/rendering/RenderObject.cpp b/Source/core/rendering/RenderObject.cpp
index de770b47f58352df427646411434c11e9aa7a979..ab14b0c2d2e54f1459a2391f50e426fb26a81aa2 100644
--- a/Source/core/rendering/RenderObject.cpp
+++ b/Source/core/rendering/RenderObject.cpp
@@ -2060,6 +2060,17 @@ void RenderObject::styleDidChange(StyleDifference diff, const RenderStyle* oldSt
     if (s_affectsParentBlock)
         handleDynamicFloatPositionChange();
 
+    if (RenderView* view = this->view()) {

[esprehn, 2013/10/25 22:25:51]

You don't need to null check this, going through styleDidChange when there's no
view should not be possible

+        bool newStyleMayHaveViewportPercentage = style()->mayHaveViewportPercentageProperty();
+        bool oldStyleMayHaveViewportPercentage = oldStyle && oldStyle->mayHaveViewportPercentageProperty();
+        if (newStyleMayHaveViewportPercentage != oldStyleMayHaveViewportPercentage) {
+            if (newStyleMayHaveViewportPercentage)
+                view->addViewportPercentageStyleObject(this);
+            else
+                view->removeViewportPercentageStyleObject(this);
+        }
+    }
+
     if (!m_parent)
         return;
 
@@ -2609,6 +2620,9 @@ void RenderObject::willBeDestroyed()
     setAncestorLineBoxDirty(false);
 
     clearLayoutRootIfNeeded();
+
+    if (RenderView* view = this->view())
+        view->removeViewportPercentageStyleObject(this);
 }
 
 void RenderObject::insertedIntoTree()