mac: Only let two-finger-scrolling trigger history if web doesn't swallow gesture

content/browser/renderer_host/render_view_host.cc

Index: content/browser/renderer_host/render_view_host.cc
diff --git a/content/browser/renderer_host/render_view_host.cc b/content/browser/renderer_host/render_view_host.cc
index 8af8ed86594def723ee00d433fbcddfe258a6ab8..463ad36b0fcce5661008cfea7ebbb6b8a5a6c776 100644
--- a/content/browser/renderer_host/render_view_host.cc
+++ b/content/browser/renderer_host/render_view_host.cc
@@ -1009,16 +1009,17 @@ void RenderViewHost::OnMsgDidContentsPreferredSizeChange(
 
 void RenderViewHost::OnMsgDidChangeScrollbarsForMainFrame(
     bool has_horizontal_scrollbar, bool has_vertical_scrollbar) {
-  // TODO(thakis): Implement, http://crbug.com/90228
+  if (view())
+    view()->SetHasHorizontalScrollbar(has_horizontal_scrollbar);
 }
 
 void RenderViewHost::OnMsgDidChangeScrollOffsetPinningForMainFrame(
     bool is_pinned_to_left, bool is_pinned_to_right) {
-  // TODO(thakis): Implement, http://crbug.com/90228
+  if (view())
+    view()->SetScrollOffsetPinning(is_pinned_to_left, is_pinned_to_right);
 }
 
 void RenderViewHost::OnMsgDidChangeNumWheelEvents(int count) {
-  // TODO(thakis): Implement, http://crbug.com/90228
 }
 
 void RenderViewHost::OnMsgSelectionChanged(const std::string& text,