fix(segment): only emit ionChange when user releases pointer from screen (#20495)

fixes #20500
fixes #20257

angular/src/directives/control-value-accessors/value-accessor.ts

@@ -12,6 +12,13 @@ export class ValueAccessor implements ControlValueAccessor {
   constructor(protected el: ElementRef) {}
 
   writeValue(value: any) {
+    /**
+     * TODO for Ionic 6:
+     * Change `value == null ? '' : value;`
+     * to `value`. This was a fix for IE9, but IE9
+     * is no longer supported; however, this change
+     * is potentially a breaking change
+     */
     this.el.nativeElement.value = this.lastValue = value == null ? '' : value;
     setIonicClasses(this.el);
   }