[polari] ui: Fix CSD window decorations

[Florian Müllner <fmuellner src gnome org>]

commit 64bc6cf34e8dba426bdf50e726b33d0e93df2d5a
Author: Florian Müllner <fmuellner gnome org>
Date:   Fri Sep 6 16:42:52 2013 +0200

    ui: Fix CSD window decorations
    
    Tricky. GTK+ automatically sets the .titlebar style on custom titlebars,
    which will give us a nice gradient background and rounded corners in
    Adwaita. Except that GtkBox we are using as container for the two
    HeaderBars does not have a window to paint on, so our titlebar ends
    up with the default header-bar style - no gradient, no rounded corners.
    Work around this by manually adding the .titlebar class to both
    HeaderBars and use custom CSS to remove the unwanted border-radii.

 data/resources/application.css |   10 ++++++++++
 data/resources/main-window.ui  |    2 ++
 2 files changed, 12 insertions(+), 0 deletions(-)
---
diff --git a/data/resources/application.css b/data/resources/application.css
index a3b3e4f..eb76b9e 100644
--- a/data/resources/application.css
+++ b/data/resources/application.css
@@ -83,6 +83,16 @@
     padding: 6px 1px 0;
 }
 
+.polari-titlebar-left:dir(ltr),
+.polari-titlebar-right:dir(rtl) {
+    border-top-right-radius: 0;
+}
+
+.polari-titlebar-right:dir(ltr),
+.polari-titlebar-left:dir(rtl) {
+    border-top-left-radius: 0;
+}
+
 .polari-titlebar-separator {
     border-image: linear-gradient(to bottom, @theme_bg_color, shade(@borders, 1.2));
     border-image-width: 0 1px 0 0;
diff --git a/data/resources/main-window.ui b/data/resources/main-window.ui
index f06946d..7e77327 100644
--- a/data/resources/main-window.ui
+++ b/data/resources/main-window.ui
@@ -31,6 +31,7 @@
             <property name="hexpand">False</property>
             <style>
               <class name="polari-titlebar-left"/>
+              <class name="titlebar"/>
             </style>
             <child>
               <object class="GtkMenuButton" id="button1">
@@ -102,6 +103,7 @@
             <property name="show_close_button">True</property>
             <style>
               <class name="polari-titlebar-right"/>
+              <class name="titlebar"/>
             </style>
             <child>
               <object class="GtkLabel" id="label1">