Route Scroll events through a cc::InputHandler

ui/compositor/BUILD.gn

 # 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.
 
 import("//build/config/ui.gni")
 import("//testing/test.gni")
 
 component("compositor") {
   sources = [
     "callback_layer_animation_observer.cc",
@@ skipping 36 matching lines @@
     "layer_animator_collection.h",
     "layer_delegate.cc",
     "layer_delegate.h",
     "layer_observer.h",
     "layer_owner.cc",
     "layer_owner.h",
     "layer_threaded_animation_delegate.h",
     "layer_tree_owner.cc",
     "layer_tree_owner.h",
     "layer_type.h",
+    "overscroll/ui_input_handler.cc",
+    "overscroll/ui_input_handler.h",
+    "overscroll/ui_scroll_input_manager.cc",
+    "overscroll/ui_scroll_input_manager.h",
     "paint_cache.cc",
     "paint_cache.h",
     "paint_context.cc",
     "paint_context.h",
     "paint_recorder.cc",
     "paint_recorder.h",
     "reflector.cc",
     "reflector.h",
     "scoped_animation_duration_scale_mode.cc",
     "scoped_animation_duration_scale_mode.h",
     "scoped_layer_animation_settings.cc",
     "scoped_layer_animation_settings.h",
     "transform_animation_curve_adapter.cc",
     "transform_animation_curve_adapter.h",
     "transform_recorder.cc",
     "transform_recorder.h",
   ]
 
   defines = [ "COMPOSITOR_IMPLEMENTATION" ]
 
   deps = [
     "//base",
     "//base/third_party/dynamic_annotations",
     "//cc",
     "//cc/animation",
     "//cc/surfaces",
     "//cc/surfaces:surface_id",
     "//gpu/command_buffer/common",
     "//skia",
+    "//ui/events",
     "//ui/gfx",
     "//ui/gfx/geometry",
     "//ui/gl",
   ]
 
   if (is_win && use_aura) {
     # TODO(sky): before we make this real need to remove
     # IDR_BITMAP_BRUSH_IMAGE.
     deps += [
       "//third_party/angle:libEGL",
@@ skipping 103 matching lines @@
     "//ui/base",
     "//ui/gfx",
     "//ui/gfx/geometry",
     "//ui/gl",
     "//ui/resources",
   ]
   if (is_linux) {
     deps += [ "//third_party/mesa:osmesa" ]
   }
 }