[epiphany] prefs-dialog: Restore mnemonics removed by mistake

[Michael Catanzaro <mcatanzaro src gnome org>]

commit aa7d3d4b570b0499b4bc13d0dc6e2f6a52e9d994
Author: Michael Catanzaro <mcatanzaro gnome org>
Date:   Sun Jan 19 09:50:05 2020 -0600

    prefs-dialog: Restore mnemonics removed by mistake

 src/resources/gtk/prefs-dialog.ui | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)
---
diff --git a/src/resources/gtk/prefs-dialog.ui b/src/resources/gtk/prefs-dialog.ui
index ed4fcb380..673a1aeed 100644
--- a/src/resources/gtk/prefs-dialog.ui
+++ b/src/resources/gtk/prefs-dialog.ui
@@ -267,7 +267,7 @@
                     <child>
                       <object class="HdyActionRow">
                         <property name="activatable_widget">start_in_incognito_mode_switch</property>
-                        <property name="title" translatable="yes">Start in Incognito Mode</property>
+                        <property name="title" translatable="yes">Start in _Incognito Mode</property>
                         <property name="use_underline">True</property>
                         <property name="visible">True</property>
                         <child type="action">
@@ -281,7 +281,7 @@
                     <child>
                       <object class="HdyActionRow" id="restore_session_row">
                         <property name="activatable_widget">restore_session_switch</property>
-                        <property name="title" translatable="yes">Restore Tabs on Startup</property>
+                        <property name="title" translatable="yes">_Restore Tabs on Startup</property>
                         <property name="use_underline">True</property>
                         <property name="visible">True</property>
                         <child type="action">
@@ -400,7 +400,7 @@
                     <child>
                       <object class="HdyActionRow">
                         <property name="activatable_widget">popups_allow_switch</property>
-                        <property name="title" translatable="yes">Block Popup Windows</property>
+                        <property name="title" translatable="yes">Block Popup _Windows</property>
                         <property name="use_underline">True</property>
                         <property name="visible">True</property>
                         <child type="action">