[geary] Fix runtime errors when built/running against GTK +3.14.

[Michael Gratton <mjog src gnome org>]

commit 3ef1ac973eb7ba1802b4166d544451d3aa1036ce
Author: Michael James Gratton <mike vee net>
Date:   Tue Dec 6 16:22:39 2016 +1100

    Fix runtime errors when built/running against GTK +3.14.
    
    * ui/conversation-viewer.ui,
      src/client/conversation-viewer/conversation-viewer.vala: next-match and
      previous-match signals are only available in GTK+ >= 3.16.
    
    * ui/empty-placeholder.ui: Drop declared GTK+ requirement to 3.14.
    
    * ui/geary.css: The :not() pseudeo class is only available in GTK+ >= 3.20.

 .../conversation-viewer/conversation-viewer.vala   |   28 ++++++++++---------
 ui/conversation-viewer.ui                          |    2 -
 ui/empty-placeholder.ui                            |    2 +-
 ui/geary.css                                       |    2 +-
 4 files changed, 17 insertions(+), 17 deletions(-)
---
diff --git a/src/client/conversation-viewer/conversation-viewer.vala 
b/src/client/conversation-viewer/conversation-viewer.vala
index 2669072..55b52a4 100644
--- a/src/client/conversation-viewer/conversation-viewer.vala
+++ b/src/client/conversation-viewer/conversation-viewer.vala
@@ -326,19 +326,21 @@ public class ConversationViewer : Gtk.Stack {
         }
     }
 
-    [GtkCallback]
-    private void on_find_next(Gtk.Widget entry) {
-        if (this.current_list != null) {
-            //this.current_list.show_prev_search_term();
-        }
-    }
-
-    [GtkCallback]
-    private void on_find_prev(Gtk.Widget entry) {
-        if (this.current_list != null) {
-            //this.current_list.show_next_search_term();
-        }
-    }
+    // XXX We can't use this signal with GTK 3.14.
+    // [GtkCallback]
+    // private void on_find_next(Gtk.Widget entry) {
+    //     if (this.current_list != null) {
+    //         //this.current_list.show_prev_search_term();
+    //     }
+    // }
+
+    // XXX We can't use this signal with GTK 3.14.
+    // [GtkCallback]
+    // private void on_find_prev(Gtk.Widget entry) {
+    //     if (this.current_list != null) {
+    //         //this.current_list.show_next_search_term();
+    //     }
+    // }
 
 }
 
diff --git a/ui/conversation-viewer.ui b/ui/conversation-viewer.ui
index 2e87072..fbb6434 100644
--- a/ui/conversation-viewer.ui
+++ b/ui/conversation-viewer.ui
@@ -58,8 +58,6 @@
                     <property name="primary_icon_activatable">False</property>
                     <property name="primary_icon_sensitive">False</property>
                     <property name="placeholder_text" translatable="yes">Find in conversation</property>
-                    <signal name="next-match" handler="on_find_next" swapped="no"/>
-                    <signal name="previous-match" handler="on_find_prev" swapped="no"/>
                     <signal name="search-changed" handler="on_find_text_changed" swapped="no"/>
                   </object>
                   <packing>
diff --git a/ui/empty-placeholder.ui b/ui/empty-placeholder.ui
index f5355f3..1de05f1 100644
--- a/ui/empty-placeholder.ui
+++ b/ui/empty-placeholder.ui
@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <!-- Generated with glade 3.20.0 -->
 <interface>
-  <requires lib="gtk+" version="3.20"/>
+  <requires lib="gtk+" version="3.14"/>
   <template class="EmptyPlaceholder" parent="GtkGrid">
     <property name="visible">True</property>
     <property name="can_focus">False</property>
diff --git a/ui/geary.css b/ui/geary.css
index b6ae1c4..e6777f8 100644
--- a/ui/geary.css
+++ b/ui/geary.css
@@ -130,7 +130,7 @@ row.geary-folder-popover-list-row > label {
   background: @theme_base_color;
 }
 
-.geary-header-value flowboxchild label:not(.geary-primary) {
+.geary-header-value flowboxchild label.dim-label {
   margin-left: 6px;
 }