Handle touchpad flings with passive event listeners on compositor thread.

content/renderer/input/input_handler_wrapper.cc

Index: content/renderer/input/input_handler_wrapper.cc
diff --git a/content/renderer/input/input_handler_wrapper.cc b/content/renderer/input/input_handler_wrapper.cc
index 6230332d726089653d6144f8e7e600a650638fe1..50f5b15b08a04c6112c2adb3312c6e558f41da71 100644
--- a/content/renderer/input/input_handler_wrapper.cc
+++ b/content/renderer/input/input_handler_wrapper.cc
@@ -46,6 +46,12 @@ void InputHandlerWrapper::TransferActiveWheelFlingAnimation(
                             render_view_impl_, params));
 }
 
+void InputHandlerWrapper::DispatchNonBlockingEventToMainThread(
+    ui::ScopedWebInputEvent event) {
+  input_handler_manager_->DispatchNonBlockingEventToMainThread(
+      routing_id_, std::move(event));
+}
+
 void InputHandlerWrapper::WillShutdown() {
   input_handler_manager_->RemoveInputHandler(routing_id_);
 }