views: use ACTION_MOVE to display correct cursor

When dragging events around, the cursors show a + as opposed to a
an arrow indicating that the event is being moved. This can confuse
users.

The fix is to tell GTK that the drag being performed is a move.

https://bugzilla.gnome.org/show_bug.cgi?id=774922

src/gcal-event-widget.c

@@ -207,7 +207,7 @@ gcal_event_widget_init (GcalEventWidget *self)
                        GDK_BUTTON1_MASK,
                        NULL,
                        0,
-                       GDK_ACTION_COPY);
+                       GDK_ACTION_MOVE);
 
   gtk_drag_source_add_text_targets (widget);
 }
@@ -843,7 +843,7 @@ gcal_event_widget_set_read_only (GcalEventWidget *event,
                            0,
                            NULL,
                            0,
-                           GDK_ACTION_COPY);
+                           GDK_ACTION_MOVE);
 
       gtk_drag_source_add_text_targets (widget);
     }

src/views/gcal-month-view.c

@@ -754,7 +754,7 @@ gcal_month_view_drag_motion (GtkWidget      *widget,
    * aborts the drag with FALSE.
    */
   gdk_drag_status (context,
-                   self->dnd_cell == -1 ? 0 : GDK_ACTION_COPY,
+                   self->dnd_cell == -1 ? 0 : GDK_ACTION_MOVE,
                    time);
 
   gtk_widget_queue_draw (widget);

src/views/gcal-week-grid.c

@@ -983,7 +983,7 @@ gcal_week_grid_drag_motion (GtkWidget      *widget,
    * aborts the drag with FALSE.
    */
   gdk_drag_status (context,
-                   self->dnd_cell == -1 ? 0 : GDK_ACTION_COPY,
+                   self->dnd_cell == -1 ? 0 : GDK_ACTION_MOVE,
                    time);
 
   gtk_widget_queue_draw (widget);

src/views/gcal-week-header.c

@@ -1383,7 +1383,7 @@ gcal_week_header_drag_motion (GtkWidget      *widget,
    * aborts the drag with FALSE.
    */
   gdk_drag_status (context,
-                   self->dnd_cell == -1 ? 0 : GDK_ACTION_COPY,
+                   self->dnd_cell == -1 ? 0 : GDK_ACTION_MOVE,
                    time);
 
   gtk_widget_queue_draw (widget);

src/views/gcal-year-view.c

@@ -1398,7 +1398,7 @@ navigator_drag_motion_cb (GcalYearView   *self,
           self->selected_data->dnd_day = day;
           self->selected_data->dnd_month = month;
 
-          gdk_drag_status (context, GDK_ACTION_COPY, time);
+          gdk_drag_status (context, GDK_ACTION_MOVE, time);
 
           retval = TRUE;
         }
@@ -1955,7 +1955,7 @@ gcal_year_view_init (GcalYearView *self)
                      0,
                      NULL,
                      0,
-                     GDK_ACTION_COPY);
+                     GDK_ACTION_MOVE);
 }
 
 static void