fix(refresher): tune threshold

fixes #15233

core/src/components/nav/test/basic/index.html

@@ -17,6 +17,9 @@
             </ion-toolbar>
           </ion-header>
           <ion-content padding>
+            <ion-refresher>
+              <ion-refresher-content></ion-refresher-content>
+            </ion-refresher>
             <h1>Page One</h1>
             <ion-nav-push component="page-two">
               <ion-button class="next">Go to Page Two</ion-button>
@@ -37,6 +40,9 @@
             </ion-toolbar>
           </ion-header>
           <ion-content padding>
+            <ion-refresher>
+              <ion-refresher-content></ion-refresher-content>
+            </ion-refresher>
             <h1>Page Two</h1>
             <div>
               <ion-nav-push component="page-three">

core/src/components/refresher/refresher.tsx

@@ -108,7 +108,7 @@ export class Refresher {
       gestureName: 'refresher',
       gesturePriority: 10,
       direction: 'y',
-      threshold: 10,
+      threshold: 20,
       passive: false,
       canStart: this.canStart.bind(this),
       onStart: this.onStart.bind(this),