Implement CSSOM Smooth Scroll API

Source/core/dom/Element.cpp

Index: Source/core/dom/Element.cpp
diff --git a/Source/core/dom/Element.cpp b/Source/core/dom/Element.cpp
index 41a571aff9a0c9bec59490b80bc32245ec66f04d..3ae6cedca335918ec21e4b3a6bce43b3fa931ad4 100644
--- a/Source/core/dom/Element.cpp
+++ b/Source/core/dom/Element.cpp
@@ -682,13 +682,13 @@ int Element::scrollTop()
     return 0;
 }
 
-void Element::setScrollLeft(int newLeft)
+void Element::setScrollLeftInternal(int newLeft, ScrollBehavior scrollBehavior)
 {
     document().updateLayoutIgnorePendingStylesheets();
 
     if (document().documentElement() != this) {
         if (RenderBox* rend = renderBox())
-            rend->setScrollLeft(roundf(newLeft * rend->style()->effectiveZoom()));
+            rend->setScrollLeft(roundf(newLeft * rend->style()->effectiveZoom()), scrollBehavior);
         return;
     }
 
@@ -703,7 +703,7 @@ void Element::setScrollLeft(int newLeft)
         if (!view)
             return;
 
-        view->setScrollPosition(IntPoint(roundf(newLeft * frame->pageZoomFactor()), view->scrollY()));
+        view->setScrollPosition(IntPoint(roundf(newLeft * frame->pageZoomFactor()), view->scrollY()), scrollBehavior);
     }
 }
 
@@ -724,17 +724,16 @@ void Element::setScrollLeft(const Dictionary& scrollOptionsHorizontal, Exception
         return;
     }
 
-    // FIXME: Use scrollBehavior to decide whether to scroll smoothly or instantly.
-    setScrollLeft(position);
+    setScrollLeft(position, scrollBehavior);
 }
 
-void Element::setScrollTop(int newTop)
+void Element::setScrollTopInternal(int newTop, ScrollBehavior scrollBehavior)
 {
     document().updateLayoutIgnorePendingStylesheets();
 
     if (document().documentElement() != this) {
         if (RenderBox* rend = renderBox())
-            rend->setScrollTop(roundf(newTop * rend->style()->effectiveZoom()));
+            rend->setScrollTop(roundf(newTop * rend->style()->effectiveZoom()), scrollBehavior);
         return;
     }
 
@@ -749,7 +748,7 @@ void Element::setScrollTop(int newTop)
         if (!view)
             return;
 
-        view->setScrollPosition(IntPoint(view->scrollX(), roundf(newTop * frame->pageZoomFactor())));
+        view->setScrollPosition(IntPoint(view->scrollX(), roundf(newTop * frame->pageZoomFactor())), scrollBehavior);
     }
 }
 
@@ -770,8 +769,7 @@ void Element::setScrollTop(const Dictionary& scrollOptionsVertical, ExceptionSta
         return;
     }
 
-    // FIXME: Use scrollBehavior to decide whether to scroll smoothly or instantly.
-    setScrollTop(position);
+    setScrollTop(position, scrollBehavior);
 }
 
 int Element::scrollWidth()