Specify "content" and "unbalanced-wikitext" as a valid parameter types

Bug: 51374
Change-Id: I711998193cc542b72213b56046529b53ebb17d73

TemplateDataBlob.php

@@ -93,9 +93,11 @@ class TemplateDataBlob {
 		);
 
 		static $types = array(
+			'content',
 			'line',
 			'number',
 			'string',
+			'unbalanced-wikitext',
 			'unknown',
 			'wiki-page-name',
 			'wiki-user-name',

spec.templatedata.json

@@ -54,6 +54,12 @@
 	- wiki-user-name
 	  A valid MediaWiki user name for the current wiki. Doesn't have to exist,
 	  but if not should be a valid user name to create.
+	- content
+	  Page content (such as text style, links and images etc.).
+	- unbalanced-wikitext
+	  Raw wikitext that should not be treated as standalone content because it
+	  is unbalanced (eg. templates concatenating incomplete wikitext as a bigger
+	  whole such as {{echo|before=<u>|after=</u>}})
 	- line
 	  Short text field - use for names, labels, and other short-form fields.