MlkBookmarkSubmissionForm: Add initializers back.

The initializers were mistakenly removed, but they are needed for
bookmarklet-driven bookmark submission.  This adds them back.

Change-Id: I565e5b3f372da826224d96dddf568295af552744
diff --git a/src/main/resources/META-INF/resources/bookmarks/MlkBookmarkSubmissionForm.js b/src/main/resources/META-INF/resources/bookmarks/MlkBookmarkSubmissionForm.js
index 84054d0..83242ba 100644
--- a/src/main/resources/META-INF/resources/bookmarks/MlkBookmarkSubmissionForm.js
+++ b/src/main/resources/META-INF/resources/bookmarks/MlkBookmarkSubmissionForm.js
@@ -85,6 +85,9 @@
     }
 
     this.uriInput.addEventListener('blur', this.onUriBlur.bind(this));
+    this.uriInput.value = this.uri || "";
+    this.titleInput.value = this.titleText || "";
+    this.descriptionInput.innerText = this.description || "";
   }
 
   get editedId() /*:number | null*/ {