Move ScrollableArea timer to TaskRunnerTimer.

third_party/WebKit/Source/platform/scroll/ScrollableArea.cpp

Index: third_party/WebKit/Source/platform/scroll/ScrollableArea.cpp
diff --git a/third_party/WebKit/Source/platform/scroll/ScrollableArea.cpp b/third_party/WebKit/Source/platform/scroll/ScrollableArea.cpp
index 0e1681ef3de8de68557b632c4ba6cd0f38871993..0d4f9f209b37894fdc03c233fb202aec0e0ebb88 100644
--- a/third_party/WebKit/Source/platform/scroll/ScrollableArea.cpp
+++ b/third_party/WebKit/Source/platform/scroll/ScrollableArea.cpp
@@ -37,6 +37,9 @@
 #include "platform/scroll/MainThreadScrollingReason.h"
 #include "platform/scroll/ProgrammaticScrollAnimator.h"
 #include "platform/scroll/ScrollbarTheme.h"
+#include "public/platform/Platform.h"
+#include "public/platform/WebScheduler.h"
+#include "public/platform/WebThread.h"
 
 static const int kPixelsPerLineStep = 40;
 static const float kMinFractionToStepWhenPaging = 0.875f;
@@ -577,8 +580,9 @@ void ScrollableArea::showOverlayScrollbars() {
     return;
 
   if (!m_fadeOverlayScrollbarsTimer) {
-    m_fadeOverlayScrollbarsTimer.reset(new Timer<ScrollableArea>(
-        this, &ScrollableArea::fadeOverlayScrollbarsTimerFired));
+    m_fadeOverlayScrollbarsTimer.reset(new TaskRunnerTimer<ScrollableArea>(
+        getTimerTaskRunner(), this,
+        &ScrollableArea::fadeOverlayScrollbarsTimerFired));
   }
 
   if (!m_scrollbarCaptured && !m_mouseOverScrollbar) {
@@ -657,6 +661,12 @@ FloatQuad ScrollableArea::localToVisibleContentQuad(const FloatQuad& quad,
   return result;
 }
 
+RefPtr<WebTaskRunner> ScrollableArea::getTimerTaskRunner() const {

[haraken, 2017/01/20 05:45:51]

I'd prefer making this a pure virtual method and override getTimerTaskRunner on
all subclasses.

[jbroman, 2017/01/20 15:55:17]

Done.

+  WebThread* thread = Platform::current()->mainThread();
+  DCHECK(thread->isCurrentThread());
+  return thread->scheduler()->timerTaskRunner();
+}
+
 IntSize ScrollableArea::excludeScrollbars(const IntSize& size) const {
   return IntSize(std::max(0, size.width() - verticalScrollbarWidth()),
                  std::max(0, size.height() - horizontalScrollbarHeight()));