Revert of Don't setStyle the RenderView every style recalc

Source/core/dom/Document.cpp

Index: Source/core/dom/Document.cpp
diff --git a/Source/core/dom/Document.cpp b/Source/core/dom/Document.cpp
index b698359de2bfac80ad6a87880b71b9e082b83002..9cd3a9f7679d3c1801f958ac83661fa97b265316 100644
--- a/Source/core/dom/Document.cpp
+++ b/Source/core/dom/Document.cpp
@@ -1660,32 +1660,28 @@
         documentElement()->setNeedsStyleRecalc(SubtreeStyleChange);
     }
 
-    EOverflow overflowX = OAUTO;
-    EOverflow overflowY = OAUTO;
-    float columnGap = 0;
-    if (overflowStyle) {
-        overflowX = overflowStyle->overflowX();
-        overflowY = overflowStyle->overflowY();
-        // Visible overflow on the viewport is meaningless, and the spec says to treat it as 'auto':
-        if (overflowX == OVISIBLE)
-            overflowX = OAUTO;
-        if (overflowY == OVISIBLE)
-            overflowY = OAUTO;
-        // Column-gap is (ab)used by the current paged overflow implementation (in lack of other
-        // ways to specify gaps between pages), so we have to propagate it too.
-        columnGap = overflowStyle->columnGap();
-    }
-
     RefPtr<RenderStyle> documentStyle = renderView()->style();
     if (documentStyle->writingMode() != rootWritingMode
         || documentStyle->direction() != rootDirection
-        || documentStyle->overflowX() != overflowX
-        || documentStyle->overflowY() != overflowY
-        || documentStyle->columnGap() != columnGap) {
+        || (overflowStyle && (documentStyle->overflowX() != overflowStyle->overflowX() || documentStyle->overflowY() != overflowStyle->overflowY()))) {
         RefPtr<RenderStyle> newStyle = RenderStyle::clone(documentStyle.get());
         newStyle->setWritingMode(rootWritingMode);
         newStyle->setDirection(rootDirection);
-        newStyle->setColumnGap(columnGap);
+        EOverflow overflowX = OAUTO;
+        EOverflow overflowY = OAUTO;
+        if (overflowStyle) {
+            overflowX = overflowStyle->overflowX();
+            overflowY = overflowStyle->overflowY();
+            // Visible overflow on the viewport is meaningless, and the spec says to treat it as 'auto':
+            if (overflowX == OVISIBLE)
+                overflowX = OAUTO;
+            if (overflowY == OVISIBLE)
+                overflowY = OAUTO;
+
+            // Column-gap is (ab)used by the current paged overflow implementation (in lack of other
+            // ways to specify gaps between pages), so we have to propagate it too.
+            newStyle->setColumnGap(overflowStyle->columnGap());
+        }
         newStyle->setOverflowX(overflowX);
         newStyle->setOverflowY(overflowY);
         renderView()->setStyle(newStyle);