addressed comments

Author: mmalerba

tools/gulp/tasks/docs.ts

@@ -37,7 +37,9 @@ const MARKDOWN_TAGS_TO_CLASS_ALIAS = [
   'table',
   'tbody',
   'td',
-  'th'
+  'th',
+  'tr',
+  'ul'
 ];
 
 task('docs', ['markdown-docs', 'highlight-docs', 'api-docs']);
@@ -57,15 +59,7 @@ task('markdown-docs', () => {
         }
       }))
       .pipe(transform(transformMarkdownFiles))
-      .pipe(dom(function () {
-        MARKDOWN_TAGS_TO_CLASS_ALIAS.forEach((tag) => {
-          Array.prototype.slice.call(this.querySelectorAll(tag)).forEach((el: any) => {
-            el.classList.add(`docs-markdown-${tag}`);
-          });
-        });
-
-        return this;
-      }))
+      .pipe(dom(createTagNameAliaser('docs-markdown')))
       .pipe(dest('dist/docs/markdown'));
 });
 
@@ -123,3 +117,20 @@ function fixMarkdownDocLinks(link: string, filePath: string): string {
   // guides can be loaded in the Material docs.
   return `guide/${baseName}`;
 }
+
+/**
+ * Returns a function to be called with an HTML document as its context that aliases HTML tags by
+ * adding a class consisting of a prefix + the tag name.
+ * @param classPrefix The prefix to use for the alias class.
+ */
+function createTagNameAliaser(classPrefix: string) {
+  return function() {
+    MARKDOWN_TAGS_TO_CLASS_ALIAS.forEach((tag) => {
+      for (let el of this.querySelectorAll(tag)) {
+        el.classList.add(`${classPrefix}-${tag}`);
+      }
+    });
+
+    return this;
+  };
+}