Setting Accurate ScrollResult from Blink for Elastic Scroll.

content/renderer/render_view_impl.cc

 // Copyright (c) 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 "content/renderer/render_view_impl.h"
 
 #include <algorithm>
 #include <cmath>
 
 #include "base/auto_reset.h"
@@ skipping 1116 matching lines @@
   WebNetworkStateNotifier::setWebConnectionType(
       NetConnectionTypeToWebConnectionType(prefs.connection_type));
 
   settings->setPinchOverlayScrollbarThickness(
       prefs.pinch_overlay_scrollbar_thickness);
   settings->setUseSolidColorScrollbars(prefs.use_solid_color_scrollbars);
 
   settings->setShowContextMenuOnMouseUp(prefs.context_menu_on_mouse_up);
 
 #if defined(OS_MACOSX)
+#if !defined(OS_IOS)
+  bool is_elastic_overscroll_enabled =
+      RenderViewImpl::FromWebView(web_view)
+          ? RenderViewImpl::FromWebView(web_view)->IsElasticOverscrollEnabled()

[piman, 2015/06/30 21:30:00]

RenderViewImpl will disappear in the future (out-of-process iframes).
It sounds like all you need here is the compositor_deps_. Can you pass those
explicitly? The callers (where web_view is for a RenderViewImpl) have one -
either RenderViewImpl::OnUpdateWebPreferences or RenderViewImpl::Initialize.

For example you can add a CompositorDependencies* parameter to this function,
maybe renaming it ApplyWebPreferencesInternal, and adding a ApplyWebPreferences
that just calls this with a NULL CompositorDependencies for the other callers.

That way, you even avoid the map lookup, and no need for
IsElasticOverscrollEnabled on the RenderWidget.

[MuVen, 2015/07/01 13:23:21]

Done. PTAL.

+          : false;
+  settings->setReportWheelOverscroll(is_elastic_overscroll_enabled);
+#endif
   settings->setDoubleTapToZoomEnabled(true);
   web_view->setMaximumLegibleScale(prefs.default_maximum_page_scale_factor);
 #endif
 }
 
 /*static*/
 RenderViewImpl* RenderViewImpl::Create(const ViewMsg_New_Params& params,
                                        CompositorDependencies* compositor_deps,
                                        bool was_created_by_renderer) {
   DCHECK(params.view_id != MSG_ROUTING_NONE);
@@ skipping 2649 matching lines @@
     std::vector<gfx::Size> sizes;
     ConvertToFaviconSizes(icon_urls[i].sizes(), &sizes);
     if (!url.isEmpty())
       urls.push_back(
           FaviconURL(url, ToFaviconType(icon_urls[i].iconType()), sizes));
   }
   SendUpdateFaviconURL(urls);
 }
 
 }  // namespace content