[gtk/wip/carlosg/scroll-controller-fixes: 2/2] gtkwidget: Forward unhandled scroll events through controllers

[Carlos Garnacho <carlosg src gnome org>]

commit c9a1adf2ccf7df5211b3c768f1361de1942e1a7b
Author: Carlos Garnacho <carlosg gnome org>
Date:   Mon Oct 21 17:10:30 2019 +0200

    gtkwidget: Forward unhandled scroll events through controllers
    
    Do just like button/motion/touch do, let the scroll events go first
    through the event handler, and fallback on the current event controllers
    afterwards.
    
    Fixes handling of bubbled scroll events in the scroll controller.

 gtk/gtkwidget.c | 11 +++++++++++
 1 file changed, 11 insertions(+)
---
diff --git a/gtk/gtkwidget.c b/gtk/gtkwidget.c
index 2848d757b5..65b168eb47 100644
--- a/gtk/gtkwidget.c
+++ b/gtk/gtkwidget.c
@@ -673,6 +673,8 @@ static gboolean _gtk_widget_run_controllers      (GtkWidget           *widget,
 static void    gtk_widget_dispatch_child_properties_changed    (GtkWidget        *object,
                                                                 guint             n_pspecs,
                                                                 GParamSpec      **pspecs);
+static gboolean         gtk_widget_real_scroll_event            (GtkWidget        *widget,
+                                                                 GdkEventScroll   *event);
 static gboolean         gtk_widget_real_button_event            (GtkWidget        *widget,
                                                                  GdkEventButton   *event);
 static gboolean         gtk_widget_real_motion_event            (GtkWidget        *widget,
@@ -1061,6 +1063,7 @@ gtk_widget_class_init (GtkWidgetClass *klass)
   klass->move_focus = gtk_widget_real_move_focus;
   klass->keynav_failed = gtk_widget_real_keynav_failed;
   klass->event = NULL;
+  klass->scroll_event = gtk_widget_real_scroll_event;
   klass->button_press_event = gtk_widget_real_button_event;
   klass->button_release_event = gtk_widget_real_button_event;
   klass->motion_notify_event = gtk_widget_real_motion_event;
@@ -7186,6 +7189,14 @@ gtk_widget_draw (GtkWidget *widget,
   cairo_restore (cr);
 }
 
+static gboolean
+gtk_widget_real_scroll_event (GtkWidget      *widget,
+                              GdkEventScroll *event)
+{
+  return _gtk_widget_run_controllers (widget, (GdkEvent *) event,
+                                      GTK_PHASE_BUBBLE);
+}
+
 static gboolean
 gtk_widget_real_button_event (GtkWidget      *widget,
                               GdkEventButton *event)