recurrence: add GcalRecurrenceModType

Instead of reusing the ECalObjModType and mixing the
prefixes all around, do this small cleanup and add a
gcal-prefixed enum.

src/views/gcal-month-view.c

@@ -774,11 +774,11 @@ gcal_month_view_drag_drop (GtkWidget      *widget,
                            guint           time)
 {
   GcalSubscriberViewPrivate *ppriv = GCAL_SUBSCRIBER_VIEW (widget)->priv;
+  GcalRecurrenceModType mod;
   GcalMonthView *self = GCAL_MONTH_VIEW (widget);
   GtkWidget *event_widget;
   GDateTime *start_dt, *end_dt, *current_dt;
   GcalEvent *event;
-  ECalObjModType mod;
   ESource *source;
   gint cell, diff;
   gint start_month, current_month;
@@ -787,7 +787,7 @@ gcal_month_view_drag_drop (GtkWidget      *widget,
 
   cell = get_dnd_cell (widget, x, y);
   event_widget = gtk_drag_get_source_widget (context);
-  mod = E_CAL_OBJ_MOD_THIS;
+  mod = GCAL_RECURRENCE_MOD_THIS_ONLY;
 
   if (!GCAL_IS_EVENT_WIDGET (event_widget))
     return FALSE;

src/views/gcal-week-grid.c

@@ -980,12 +980,12 @@ gcal_week_grid_drag_drop (GtkWidget      *widget,
                           gint            y,
                           guint           time)
 {
+  GcalRecurrenceModType mod;
   GcalWeekGrid *self;
   g_autoptr (GDateTime) week_start;
   g_autoptr (GDateTime) dnd_date;
   g_autoptr (GDateTime) new_end;
   GtkWidget *event_widget;
-  ECalObjModType mod;
   GcalEvent *event;
   ESource *source;
   GTimeSpan timespan = 0;
@@ -997,7 +997,7 @@ gcal_week_grid_drag_drop (GtkWidget      *widget,
   drop_cell = get_dnd_cell (widget, x, y);
   event_widget = gtk_drag_get_source_widget (context);
 
-  mod = E_CAL_OBJ_MOD_THIS;
+  mod = GCAL_RECURRENCE_MOD_THIS_ONLY;
   week_start = NULL;
   dnd_date = NULL;
   new_end = NULL;

src/views/gcal-week-header.c

@@ -1407,7 +1407,7 @@ gcal_week_header_drag_drop (GtkWidget      *widget,
     gcal_event_set_all_day (event, TRUE);
 
   /* Commit the changes */
-  gcal_manager_update_event (self->manager, event, E_CAL_OBJ_MOD_THIS);
+  gcal_manager_update_event (self->manager, event, GCAL_RECURRENCE_MOD_THIS_ONLY);
 
   /* Cancel the DnD */
   self->dnd_cell = -1;

src/views/gcal-year-view.c

@@ -1488,8 +1488,8 @@ navigator_drag_drop_cb (GcalYearView   *self,
 
       if (!is_title)
         {
+          GcalRecurrenceModType mod;
           GcalEventWidget *event_widget;
-          ECalObjModType mod;
           GcalEvent *event;
           GDateTime *start_dt, *end_dt;
           GDateTime *drop_date;
@@ -1498,7 +1498,7 @@ navigator_drag_drop_cb (GcalYearView   *self,
           event_widget = GCAL_EVENT_WIDGET (gtk_drag_get_source_widget (context));
           event = gcal_event_widget_get_event (event_widget);
           source = gcal_event_get_source (event);
-          mod = E_CAL_OBJ_MOD_THIS;
+          mod = GCAL_RECURRENCE_MOD_THIS_ONLY;
 
           if (gcal_event_has_recurrence (event) &&
               !ask_recurrence_modification_type (GTK_WIDGET (self), &mod, source))