[epiphany] Drop "About" entry in Pantheon

[Michael Catanzaro <mcatanzaro src gnome org>]

commit f2360307691671a735e3b853b17ac9febee45b52
Author: Jan-Michael Brummer <jan brummer tabos org>
Date:   Thu Dec 20 23:27:41 2018 +0100

    Drop "About" entry in Pantheon
    
    Fixes: https://gitlab.gnome.org/GNOME/epiphany/issues/72

 src/ephy-header-bar.c                  | 3 +++
 src/resources/gtk/page-menu-popover.ui | 5 +++--
 2 files changed, 6 insertions(+), 2 deletions(-)
---
diff --git a/src/ephy-header-bar.c b/src/ephy-header-bar.c
index bda11d7c9..cd119088c 100644
--- a/src/ephy-header-bar.c
+++ b/src/ephy-header-bar.c
@@ -234,6 +234,9 @@ ephy_header_bar_constructed (GObject *object)
       gtk_widget_destroy (GTK_WIDGET (gtk_builder_get_object (builder, "help-button")));
   }
 
+  if (is_desktop_pantheon ())
+    gtk_widget_destroy (GTK_WIDGET (gtk_builder_get_object (builder, "about-button")));
+
   gtk_menu_button_set_popover (GTK_MENU_BUTTON (button), page_menu_popover);
   g_object_unref (builder);
 
diff --git a/src/resources/gtk/page-menu-popover.ui b/src/resources/gtk/page-menu-popover.ui
index 28664e133..6dff125a0 100644
--- a/src/resources/gtk/page-menu-popover.ui
+++ b/src/resources/gtk/page-menu-popover.ui
@@ -262,7 +262,7 @@
             <property name="visible">True</property>
           </object>
         </child>
-        <!-- FRAGILE: This button is manually removed for app mode in ephy-header-bar.c. -->
+        <!-- FRAGILE: This button is manually removed for app mode/Pantheon in ephy-header-bar.c. -->
         <child>
           <object class="GtkModelButton" id="help-button">
             <property name="can_focus">True</property>
@@ -271,8 +271,9 @@
             <property name="visible">True</property>
           </object>
         </child>
+        <!-- FRAGILE: This button is manually removed for Pantheon in ephy-header-bar.c. -->
         <child>
-          <object class="GtkModelButton">
+          <object class="GtkModelButton" id="about-button">
             <property name="can_focus">True</property>
             <property name="text" translatable="yes">_About Web</property>
             <property name="action-name">app.about</property>