[change] Linking API

Linking updates the application document's URL rather than opening a new
window. This change also makes deep-linking work.

packages/react-native-web/src/exports/Linking/index.js

@@ -9,6 +9,7 @@
  */
 
 import { canUseDOM } from 'fbjs/lib/ExecutionEnvironment';
+import invariant from 'fbjs/lib/invariant';
 
 const initialURL = canUseDOM ? window.location.href : '';
 
@@ -28,19 +29,16 @@ const Linking = {
     } catch (e) {
       return Promise.reject(e);
     }
+  },
+  _validateURL(url: string) {
+    invariant(typeof url === 'string', 'Invalid URL: should be a string. Was: ' + url);
+    invariant(url, 'Invalid URL: cannot be empty');
   }
 };
 
 const open = url => {
-  const anchor = document.createElement('a');
-  anchor.target = '_blank'; // :(
-  anchor.rel = 'noopener';
-  anchor.href = url;
-  const body = document.body;
-  if (body) {
-    body.appendChild(anchor);
-    anchor.click();
-    body.removeChild(anchor);
+  if (canUseDOM) {
+    window.location = new URL(url, window.location).toString();
   }
 };