Implement Element.scrollIntoView for scroll-behavior: smooth.

third_party/WebKit/Source/core/frame/FrameView.cpp

Index: third_party/WebKit/Source/core/frame/FrameView.cpp
diff --git a/third_party/WebKit/Source/core/frame/FrameView.cpp b/third_party/WebKit/Source/core/frame/FrameView.cpp
index db2ee4b233d8dab7ebc5736b177856ad63136137..746b01b04c40e49660c88a3fc24107459abfceed 100644
--- a/third_party/WebKit/Source/core/frame/FrameView.cpp
+++ b/third_party/WebKit/Source/core/frame/FrameView.cpp
@@ -2102,6 +2102,13 @@ HostWindow* FrameView::getHostWindow() const {
   return &page->chromeClient();
 }
 
+SmoothScrollSequencer* FrameView::getSmoothScrollSequencer() const {
+  Page* page = frame().page();
+  if (!page)
+    return nullptr;
+  return page->smoothScrollSequencer();
+}
+
 void FrameView::contentsResized() {
   if (m_frame->isMainFrame() && m_frame->document()) {
     if (TextAutosizer* textAutosizer = m_frame->document()->textAutosizer())
@@ -4496,16 +4503,21 @@ FrameViewBase* FrameView::getFrameViewBase() {
 LayoutRect FrameView::scrollIntoView(const LayoutRect& rectInContent,
                                      const ScrollAlignment& alignX,
                                      const ScrollAlignment& alignY,
-                                     ScrollType scrollType) {
+                                     ScrollType scrollType,
+                                     bool isSmooth) {
   LayoutRect viewRect(visibleContentRect());
   LayoutRect exposeRect =
       ScrollAlignment::getRectToExpose(viewRect, rectInContent, alignX, alignY);
   if (exposeRect != viewRect) {
-    setScrollOffset(
-        ScrollOffset(exposeRect.x().toFloat(), exposeRect.y().toFloat()),
-        scrollType);
+    ScrollOffset targetOffset(exposeRect.x().toFloat(),
+                              exposeRect.y().toFloat());
+    if (isSmooth) {
+      DCHECK(scrollType != UserScroll);
+      getSmoothScrollSequencer()->queueAnimation(this, targetOffset);
+    } else {
+      setScrollOffset(targetOffset, scrollType);
+    }
   }
-

[bokan, 2017/04/07 15:56:52]

Nit: the blank line was fine

[sunyunjia, 2017/05/12 18:40:25]

Done.

   // Scrolling the FrameView cannot change the input rect's location relative to
   // the document.
   return rectInContent;