Resolve protocol http, https when not in lowercase (#21396)

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Pull Request resolved: #21396

Differential Revision: D10119630

Pulled By: RSNara

fbshipit-source-id: d0fe193eee976b9b18a2eb467b5f3af48bd7d2de

Author: hyunjongL

Libraries/Linking/Linking.js

@@ -57,6 +57,13 @@ class Linking extends NativeEventEmitter {
    * See https://facebook.github.io/react-native/docs/linking.html#openurl
    */
   openURL(url: string): Promise<any> {
+    // Android Intent requires protocols http and https to be in lowercase.
+    // https:// and http:// works, but Https:// and Http:// doesn't.
+    if (url.toLowerCase().startsWith('https://')) {
+      url = url.replace(url.substr(0, 8), 'https://');
+    } else if (url.toLowerCase().startsWith('http://')) {
+      url = url.replace(url.substr(0, 7), 'http://');
+    }
     this._validateURL(url);
     return LinkingManager.openURL(url);
   }