SetNeedsRedraw directly when updating a visible tile.

cc/test/delayed_raster_picture_pile_impl.cc

Index: cc/test/delayed_raster_picture_pile_impl.cc
diff --git a/cc/test/delayed_raster_picture_pile_impl.cc b/cc/test/delayed_raster_picture_pile_impl.cc
new file mode 100644
index 0000000000000000000000000000000000000000..c086f1a0f45a49707b2369cef99e2f8304202215
--- /dev/null
+++ b/cc/test/delayed_raster_picture_pile_impl.cc
@@ -0,0 +1,28 @@
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "cc/test/delayed_raster_picture_pile_impl.h"
+
+#include "cc/test/delayed_raster_trigger.h"
+
+namespace cc {
+
+DelayedRasterPicturePileImpl::DelayedRasterPicturePileImpl(
+    PicturePileBase* other,
+    DelayedRasterTrigger* trigger)
+    : PicturePileImpl(other), trigger_(trigger) {
+}
+
+DelayedRasterPicturePileImpl::~DelayedRasterPicturePileImpl() {
+}
+
+void DelayedRasterPicturePileImpl::PlaybackToCanvas(
+    SkCanvas* canvas,
+    const gfx::Rect& canvas_rect,
+    float contents_scale) const {
+  PicturePileImpl::PlaybackToCanvas(canvas, canvas_rect, contents_scale);
+  trigger_->Delay();
+}
+
+}  // namespace cc