add barlow font (#26477)

README

@@ -95,6 +95,13 @@ copyright notices:
   #
   # https://gitlab.gnome.org/GNOME/cantarell-fonts/blob/master/COPYING
 
+* Barlow font
+  # Copyright 2017 The Barlow Project Authors (https://github.com/jpt/barlow)
+  #
+  # This Font Software is licensed under the SIL Open Font License, Version 1.1.
+  #
+  # https://www.fontsquirrel.com/license/barlow
+
 ~~~~
 
 Some theme variant files have their own specific licenses; refer to

static/includes/_font-barlow.scss

@@ -0,0 +1,36 @@
+$barlow-font-path: '../fonts/Barlow' !default;
+
+@mixin barlow-font($type, $weight, $style: normal) {
+    @font-face {
+        font-family: 'Barlow';
+        src: url('#{$barlow-font-path}/Barlow-#{$type}-webfont.woff') format('woff');
+        font-weight: $weight;
+        font-style: $style;
+    }
+    @font-face {
+        font-family: 'Barlow Condensed';
+        src: url('#{$barlow-font-path}/BarlowCondensed-#{$type}-webfont.woff') format('woff');
+        font-weight: $weight;
+        font-style: $style;
+    }
+    @font-face {
+        font-family: 'Barlow Semi Condensed';
+        src: url('#{$barlow-font-path}/BarlowSemiCondensed-#{$type}-webfont.woff') format('woff');
+        font-weight: $weight;
+        font-style: $style;
+    }
+}
+
+@mixin barlow-font-pair($type, $weight) {
+    @include barlow-font($type, $weight);
+    @include barlow-font(#{$type}Italic, $weight, italic);
+}
+
+@include barlow-font-pair('Thin', 100);
+@include barlow-font-pair('ExtraLight', 200);
+@include barlow-font-pair('Light', 300);
+@include barlow-font-pair('Regular', 400);
+@include barlow-font-pair('Medium', 500);
+@include barlow-font-pair('SemiBold', 600);
+@include barlow-font-pair('Bold', 700);
+@include barlow-font-pair('Black', 900);