fix(grid): add requested changes

Author: MonikaKirkova

projects/igniteui-angular/src/lib/data-operations/filtering-condition.ts

@@ -24,7 +24,7 @@ export class IgxFilteringOperand {
             isUnary: false,
             iconName: 'is-in',
             hidden: true,
-            logic: (target: any, searchVal: Set<any>, ignoreCase: boolean) => this.findValueInSet(target, searchVal, ignoreCase)
+            logic: (target: any, searchVal: Set<any>) => this.findValueInSet(target, searchVal)
         }];
     }
 
@@ -60,9 +60,8 @@ export class IgxFilteringOperand {
     /**
      * @hidden
      */
-    protected findValueInSet(target: any, searchVal: Set<any>, ignoreCase?: boolean) {
-        searchVal = new Set(Array.from(searchVal).map((item) => IgxStringFilteringOperand.applyIgnoreCase(item, ignoreCase)));
-        return searchVal.has(IgxStringFilteringOperand.applyIgnoreCase(target, ignoreCase));
+    protected findValueInSet(target: any, searchVal: Set<any>) {
+        return searchVal.has(target);
     }
 }
 

projects/igniteui-angular/src/lib/grids/filtering/excel-style/excel-style-filtering.component.ts

@@ -556,7 +556,7 @@ export class IgxGridExcelStyleFilteringComponent extends BaseFilteringComponent
         this.filterValues = this.generateFilterValues();
         this.generateListData();
         this.expressionsList.forEach(expr => {
-            if (expr.expression.condition.name === 'in' && this.column.dataType === GridColumnDataType.String) {
+            if (this.column.dataType === GridColumnDataType.String && this.column.filteringIgnoreCase && expr.expression.searchVal) {
                 this.modifyExpression(expr);
             }
         });