Changing animate to beginFrame and use struct rather than naked double to allow extension.

Source/core/page/AutoscrollController.cpp

Index: Source/core/page/AutoscrollController.cpp
diff --git a/Source/core/page/AutoscrollController.cpp b/Source/core/page/AutoscrollController.cpp
index b168e004358d3900383afe94cb11b03e3400d767..0a45e1e756ca3f4fc53a46577920aba94f3563fa 100644
--- a/Source/core/page/AutoscrollController.cpp
+++ b/Source/core/page/AutoscrollController.cpp
@@ -215,7 +215,7 @@ bool AutoscrollController::panScrollInProgress() const
 
 // FIXME: This would get get better animation fidelity if it used the monotonicFrameBeginTime instead
 // of WTF::currentTime().
-void AutoscrollController::animate(double)
+void AutoscrollController::animate(blink::WebFrameTime frameTime)
 {
     if (!m_autoscrollRenderer) {
         stopAutoscroll();
@@ -225,7 +225,7 @@ void AutoscrollController::animate(double)
     EventHandler& eventHandler = m_autoscrollRenderer->frame()->eventHandler();
     switch (m_autoscrollType) {
     case AutoscrollForDragAndDrop:
-        if (WTF::currentTime() - m_dragAndDropAutoscrollStartTime > autoscrollDelay)
+        if (frameTime.displayFrameTime - m_dragAndDropAutoscrollStartTime > autoscrollDelay)

[picksi, 2014/06/24 10:10:26]

Not sure on the rules as to why WebFrametime is a struct as opposed to a class,
but it might be nice to add a timeElapsedSince() function to WebFrameTime to
avoid exposing implementation details and improve readability, so this line
would become:
if (frameTime.timeElapsedSince(m_dragAndDropAutoscrollStartTime) >
autoscrollDelay)

[mithro-old, 2014/07/01 06:04:41]

See my previous comments.

             m_autoscrollRenderer->autoscroll(m_dragAndDropAutoscrollReferencePosition);
         break;
     case AutoscrollForSelection: