[Minor] Use <sup> tag for help icon in web UI page header

This small commit makes the `(?)` web UI help link into a superscript, which should address feedback that the current design makes it look like an error occurred or like information is missing. Before: ![image](https://cloud.githubusercontent.com/assets/50748/5370611/a3ed0034-7fd9-11e4-870f-05bd9faad5b9.png) After: ![image](https://cloud.githubusercontent.com/assets/50748/5370602/6c5ca8d6-7fd9-11e4-8d1a-568d71290aa7.png) Author: Josh Rosen <joshrosen@databricks.com> Closes #3659 from JoshRosen/webui-help-sup and squashes the following commits: bd72899 [Josh Rosen] Use <sup> tag for help icon in web UI page header.

[Minor] Use <sup> tag for help icon in web UI page header
f79c1cfc · Josh Rosen · 9bd9334f · f79c1cfc
Commit f79c1cfc authored 10 years ago by Josh Rosen
--- a/core/src/main/scala/org/apache/spark/ui/UIUtils.scala
+++ b/core/src/main/scala/org/apache/spark/ui/UIUtils.scala
@@ -181,7 +181,9 @@ private[spark] object UIUtils extends Logging {
      </li>
    }
    val helpButton: Seq[Node] = helpText.map { helpText =>
-      <a data-toggle="tooltip" data-placement="bottom" title={helpText}>(?)</a>
+      <sup>
+        (<a data-toggle="tooltip" data-placement="bottom" title={helpText}>?</a>)
+      </sup>
    }.getOrElse(Seq.empty)

    <html>