Purge the ScrollBlocksOn code.

cc/layers/scrollbar_layer_unittest.cc

 // Copyright 2012 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 <stddef.h>
 
 #include <unordered_map>
 
 #include "base/thread_task_runner_handle.h"
 #include "cc/animation/scrollbar_animation_controller.h"
@@ skipping 144 matching lines @@
   LayerImpl* layer_impl_tree_root = LayerImplForScrollAreaAndScrollbar(
       layer_settings(), layer_tree_host_.get(), std::move(scrollbar), false,
       false, 0, 0);
   PaintedScrollbarLayerImpl* scrollbar_layer_impl =
       static_cast<PaintedScrollbarLayerImpl*>(
           layer_impl_tree_root->children()[1].get());
 
   // When the scrollbar is not an overlay scrollbar, the scroll should be
   // responded to on the main thread as the compositor does not yet implement
   // scrollbar scrolling.
-  InputHandler::ScrollStatus status = scrollbar_layer_impl->TryScroll(
-      gfx::PointF(), InputHandler::GESTURE, SCROLL_BLOCKS_ON_NONE);
+  InputHandler::ScrollStatus status =
+      scrollbar_layer_impl->TryScroll(gfx::PointF(), InputHandler::GESTURE);
   EXPECT_EQ(InputHandler::SCROLL_ON_MAIN_THREAD, status.thread);
   EXPECT_EQ(MainThreadScrollingReason::kScrollbarScrolling,
             status.main_thread_scrolling_reasons);
 
   // Create and attach an overlay scrollbar.
   scrollbar.reset(new FakeScrollbar(false, false, true));
 
   layer_impl_tree_root = LayerImplForScrollAreaAndScrollbar(
       layer_settings(), layer_tree_host_.get(), std::move(scrollbar), false,
       false, 0, 0);
   scrollbar_layer_impl = static_cast<PaintedScrollbarLayerImpl*>(
       layer_impl_tree_root->children()[1].get());
 
   // The user shouldn't be able to drag an overlay scrollbar and the scroll
   // may be handled in the compositor.
-  status = scrollbar_layer_impl->TryScroll(gfx::PointF(), InputHandler::GESTURE,
-                                           SCROLL_BLOCKS_ON_NONE);
+  status =
+      scrollbar_layer_impl->TryScroll(gfx::PointF(), InputHandler::GESTURE);
   EXPECT_EQ(InputHandler::SCROLL_IGNORED, status.thread);
   EXPECT_EQ(MainThreadScrollingReason::kNotScrollable,
             status.main_thread_scrolling_reasons);
 }
 
 TEST_F(ScrollbarLayerTest, ScrollOffsetSynchronization) {
   scoped_ptr<Scrollbar> scrollbar(new FakeScrollbar);
   scoped_refptr<Layer> layer_tree_root = Layer::Create(layer_settings());
   scoped_refptr<Layer> scroll_layer = Layer::Create(layer_settings());
   scoped_refptr<Layer> content_layer = Layer::Create(layer_settings());
@@ skipping 815 matching lines @@
   TestScale(gfx::Rect(1240, 0, 15, 1333), 2.7754839f);
   TestScale(gfx::Rect(1240, 0, 15, 677), 2.46677136f);
 
   // Horizontal Scrollbars.
   TestScale(gfx::Rect(0, 1240, 1333, 15), 2.7754839f);
   TestScale(gfx::Rect(0, 1240, 677, 15), 2.46677136f);
 }
 
 }  // namespace
 }  // namespace cc