Add http+https checks to validation

Author: marcoscaceres

index.html

@@ -197,9 +197,6 @@ 
                 li>
                 <li>Assert: |url| is {{URL}}.
                 li>
-                <li>If |url|'s [=URL/scheme=] is not "http" or "https", return
-                <a>a promise rejected witha> {{TypeError}}.
-                li>
                 <li>Set |data| to a copy of |data|, with its {{ShareData/url}}
                 member set to the result of running the <a>URL serializera>
                 on |url|.
@@ -308,6 +305,9 @@ 
                 li>
                 <li>If |url| is failure, return false.
                 li>
+                <li>If |url|'s [=URL/scheme=] is not "http" or "https", return
+                return false.
+                li>
               ol>
             li>
             <li>Return true.
@@ -553,8 +553,7 @@ 
             when information should be confidential, so forwarding any content
             presents a risk. In particular, the {{ShareData/title}} might be
             used by an attacker to trick a user into misinterpreting the nature
-            of the content.
-