fix(bidir): expose getter for rtl check

Closes #5903

Author: Aleksandyr

CHANGELOG.md

@@ -106,8 +106,6 @@ All notable changes for each version of this project will be documented in this
     @include igx-progress-circular($theme);
     ```
     - RTL support
-- `IgxLinearProgressBar`:
-    - RTL support
 
 ## 8.2.6
 

projects/igniteui-angular/src/lib/progressbar/progressbar.component.ts

@@ -762,7 +762,7 @@ export class IgxCircularProgressBarComponent extends BaseProgress implements Aft
     }
 
     private getProgress(percentage: number) {
-        return this._directionality.value === 'rtl' ?
+        return this._directionality.rtl ?
             this._circumference + (percentage * this._circumference / 100) :
             this._circumference - (percentage * this._circumference / 100);
     }

projects/igniteui-angular/src/lib/services/direction/directionality.ts

@@ -50,6 +50,10 @@ export class IgxDirectionality {
         return this._document;
     }
 
+    public get rtl() {
+        return this._dir === 'rtl';
+    }
+
     constructor(@Inject(DIR_DOCUMENT) document) {
         this._document = <Document>document;
         const bodyDir = this._document.body ? this._document.body.dir : null;