feat: Update fetch mixin to support region input (#1328) (#1626)

* fix: Update fetch mixin to support region input

* fix: Update changelog and documentation

Author: castastrophe

CHANGELOG-1.x.md

@@ -1,6 +1,7 @@
 # 1.8.0 (2021)
 
-- [](https://github.com/patternfly/patternfly-elements/commit/) feat: pfe-icon now supports setting default icon sets
+- [f1c1176](https://github.com/patternfly/patternfly-elements/commit/f1c1176d9278d6e5b8066b42fc040ea01d98ecb2) feat: pfe-icon now supports setting default icon sets
+- [](https://github.com/patternfly/patternfly-elements/commit/) feat: Update fetch mixin to support region input (#1328)
 - [56eb55e](https://github.com/patternfly/patternfly-elements/commit/56eb55ec8b4b62aee7d36950d158229cbf50ddef) fix: pfe-accordion IE11 regression; background context should always be white with black text
 
 # 1.7.0 (2021-05-10)

elements/pfe-sass/functions/_custom-properties.scss

@@ -127,19 +127,23 @@
 /// Returns the value (only) of a property from the respective maps
 /// Similar to pfe-var, but does not include css variable in the compiled CSS
 /// @param {String} $name - Name of the key for the map
+/// @param {String} $region - Identifies the region or slot to which this is assigned
 /// @see $pfe-vars
 /// @see $pfe-colors
 /// @see $pfe-broadcasted
 /// @example - scss - In your component styles
 ///   .my-element {
 ///     background-color: pfe-fetch( ui-base );
 ///   }
-@function pfe-fetch($name) {
+@function pfe-fetch($name, $region: null) {
     $var-name: to-string($name, "--");
-    @if map-get($LOCAL-VARIABLES, $var-name) != null {
+    @if $region != null and map-deep-get($LOCAL-VARIABLES, $region, $var-name) != null {
+        @return map-deep-get($LOCAL-VARIABLES, $region, $var-name);
+    }
+    @else if $region == null and map-get($LOCAL-VARIABLES, $var-name) != null {
         @return map-get($LOCAL-VARIABLES, $var-name);
     }
-    @if map-get($pfe-vars, $var-name) != null {
+    @else if map-get($pfe-vars, $var-name) != null {
         @return map-get($pfe-vars, $var-name);
     }
     @else if map-get($pfe-colors, $var-name) != null {