Implement CSSOM Smooth Scroll API

Source/core/frame/LocalDOMWindow.cpp

Index: Source/core/frame/LocalDOMWindow.cpp
diff --git a/Source/core/frame/LocalDOMWindow.cpp b/Source/core/frame/LocalDOMWindow.cpp
index ed9a8f2e6811923007d013922095cb82826c7984..5ce70e8d18be6f6eee9ecfd0d9bd55e92c803e8f 100644
--- a/Source/core/frame/LocalDOMWindow.cpp
+++ b/Source/core/frame/LocalDOMWindow.cpp
@@ -1384,7 +1384,7 @@ static bool scrollBehaviorFromScrollOptions(const Dictionary& scrollOptions, Scr
     return false;
 }
 
-void LocalDOMWindow::scrollBy(int x, int y) const
+void LocalDOMWindow::scrollBy(int x, int y, ScrollBehavior scrollBehavior) const
 {
     if (!isCurrentlyDisplayedInFrame())
         return;
@@ -1397,7 +1397,7 @@ void LocalDOMWindow::scrollBy(int x, int y) const
 
     IntSize scaledOffset(x * m_frame->pageZoomFactor(), y * m_frame->pageZoomFactor());
     // FIXME: Use scrollBehavior to decide whether to scroll smoothly or instantly.
-    view->scrollBy(scaledOffset);
+    view->scrollBy(scaledOffset, scrollBehavior);
 }
 
 void LocalDOMWindow::scrollBy(int x, int y, const Dictionary& scrollOptions, ExceptionState &exceptionState) const
@@ -1405,10 +1405,10 @@ void LocalDOMWindow::scrollBy(int x, int y, const Dictionary& scrollOptions, Exc
     ScrollBehavior scrollBehavior = ScrollBehaviorAuto;
     if (!scrollBehaviorFromScrollOptions(scrollOptions, scrollBehavior, exceptionState))
         return;
-    scrollBy(x, y);
+    scrollBy(x, y, scrollBehavior);
 }
 
-void LocalDOMWindow::scrollTo(int x, int y) const
+void LocalDOMWindow::scrollTo(int x, int y, ScrollBehavior scrollBehavior) const
 {
     if (!isCurrentlyDisplayedInFrame())
         return;
@@ -1421,7 +1421,7 @@ void LocalDOMWindow::scrollTo(int x, int y) const
 
     IntPoint layoutPos(x * m_frame->pageZoomFactor(), y * m_frame->pageZoomFactor());
     // FIXME: Use scrollBehavior to decide whether to scroll smoothly or instantly.
-    view->setScrollPosition(layoutPos);
+    view->setScrollPosition(layoutPos, scrollBehavior);
 }
 
 void LocalDOMWindow::scrollTo(int x, int y, const Dictionary& scrollOptions, ExceptionState& exceptionState) const
@@ -1429,7 +1429,7 @@ void LocalDOMWindow::scrollTo(int x, int y, const Dictionary& scrollOptions, Exc
     ScrollBehavior scrollBehavior = ScrollBehaviorAuto;
     if (!scrollBehaviorFromScrollOptions(scrollOptions, scrollBehavior, exceptionState))
         return;
-    scrollTo(x, y);
+    scrollTo(x, y, scrollBehavior);
 }
 
 void LocalDOMWindow::moveBy(float x, float y) const