Update WHATWG links to use HTTPS

Extracted this out of #5649

This commit was created with the following commands:

```
find . -iname "*.webidl" -type f -print0 | xargs -0 sed -i '' 's/http:\(.*\)whatwg.org/https:\1whatwg.org/g'
```

```
find . -iname "*.rs" -type f -print0 | xargs -0 sed -i '' 's/http:\(.*\)whatwg.org/https:\1whatwg.org/g'
```

1 files changed, 4 insertions, 4 deletions

diff --git a/components/script/dom/domimplementation.rs b/components/script/dom/domimplementation.rs
index e5cac62f4e7..22f853bd2ab 100644
--- a/components/script/dom/domimplementation.rs
+++ b/components/script/dom/domimplementation.rs
@@ -47,9 +47,9 @@ impl DOMImplementation {
     }
 }
 
-// http://dom.spec.whatwg.org/#domimplementation
+// https://dom.spec.whatwg.org/#domimplementation
 impl<'a> DOMImplementationMethods for JSRef<'a, DOMImplementation> {
-    // http://dom.spec.whatwg.org/#dom-domimplementation-createdocumenttype
+    // https://dom.spec.whatwg.org/#dom-domimplementation-createdocumenttype
     fn CreateDocumentType(self, qualified_name: DOMString, pubid: DOMString, sysid: DOMString)
                           -> Fallible<Temporary<DocumentType>> {
         try!(validate_qualified_name(&qualified_name));
@@ -57,7 +57,7 @@ impl<'a> DOMImplementationMethods for JSRef<'a, DOMImplementation> {
         Ok(DocumentType::new(qualified_name, Some(pubid), Some(sysid), document.r()))
     }
 
-    // http://dom.spec.whatwg.org/#dom-domimplementation-createdocument
+    // https://dom.spec.whatwg.org/#dom-domimplementation-createdocument
     fn CreateDocument(self, namespace: Option<DOMString>, qname: DOMString,
                       maybe_doctype: Option<JSRef<DocumentType>>) -> Fallible<Temporary<Document>> {
         let doc = self.document.root();
@@ -104,7 +104,7 @@ impl<'a> DOMImplementationMethods for JSRef<'a, DOMImplementation> {
         Ok(Temporary::from_rooted(doc.r()))
     }
 
-    // http://dom.spec.whatwg.org/#dom-domimplementation-createhtmldocument
+    // https://dom.spec.whatwg.org/#dom-domimplementation-createhtmldocument
     fn CreateHTMLDocument(self, title: Option<DOMString>) -> Temporary<Document> {
         let document = self.document.root();
         let win = document.r().window().root();