fix(position-strategies): check for defined offset

Author: RivaIvanova

projects/igniteui-angular/src/lib/services/overlay/position/connected-positioning-strategy.ts

@@ -27,8 +27,7 @@ export class ConnectedPositioningStrategy implements IPositionStrategy {
     verticalStartPoint: VerticalAlignment.Bottom,
     openAnimation: scaleInVerTop,
     closeAnimation: scaleOutVerTop,
-    minSize: { width: 0, height: 0 },
-    offset: 0
+    minSize: { width: 0, height: 0 }
   };
 
   constructor(settings?: PositionSettings) {

projects/igniteui-angular/src/lib/services/overlay/utilities.ts

@@ -349,6 +349,10 @@ export class Util {
             return connectedFit.horizontalOffset;
         }
 
+        if (settings.offset == null) {
+            return 0;
+        }
+
         if (
             settings.horizontalDirection === HorizontalAlignment.Left &&
             settings.horizontalStartPoint === HorizontalAlignment.Left
@@ -373,6 +377,10 @@ export class Util {
             return connectedFit.verticalOffset;
         }
 
+        if (settings.offset == null) {
+            return 0;
+        }
+
         if (
             settings.verticalDirection === VerticalAlignment.Top &&
             settings.verticalStartPoint === VerticalAlignment.Top