Fix behavior when tapping on a same-page anchor link

Turbolinks/WebView.js

@@ -54,7 +54,11 @@
         // Adapter interface
 
         visitProposedToLocationWithAction: function(location, action) {
-            this.postMessage("visitProposed", { location: location.absoluteURL, action: action })
+            if (this.controller.locationIsSamePageAnchor(location)) {
+                this.controller.scrollToAnchor(location.anchor)
+            } else {
+                this.postMessage("visitProposed", { location: location.absoluteURL, action: action })
+            }
         },
 
         visitStarted: function(visit) {

TurbolinksDemo/server/lib/turbolinks_demo/views/index.erb

@@ -6,6 +6,11 @@
   <li><a href="/nonexistent">Trigger an HTTP 404</a> to see how Turbolinks handles error responses.</li>
   <li><a href="/protected">Visit a protected area</a> to see how to handle an unauthorized session using a separate web view.</li>
   <li><a href="/numbers">Load a native view controller</a> to see how to intercept the URL and handle it natively.</li>
+  <li><a href="#same-page-anchor">Scroll to an element on this page</a>.</li>
   <li><a href="https://github.com/turbolinks/turbolinks" target="_blank">Follow an external link</a> to open it in Safari.</li>
   <li><a href="#" data-behavior="post-message">Post a message from JavaScript</a> to see how it can be handled natively.</li>
 </ul>
+
+<div id="same-page-anchor" style="margin-top: 100vh; height: 100vh">
+  Same-page anchor. <a href="#">Back to top</a>.
+</div>