Fix IntroPreference summary visibility

The summary view should be GONE if the summary is null or empty.

Bug: 376561356
Change-Id: I42fa6b46a3575eac1cd9f423e6a8af18a7ce9385
Test: manual
Flag: EXEMPT bug fix
diff --git a/packages/SettingsLib/IntroPreference/src/com/android/settingslib/widget/IntroPreference.kt b/packages/SettingsLib/IntroPreference/src/com/android/settingslib/widget/IntroPreference.kt
index 8133761..f9931cf 100644
--- a/packages/SettingsLib/IntroPreference/src/com/android/settingslib/widget/IntroPreference.kt
+++ b/packages/SettingsLib/IntroPreference/src/com/android/settingslib/widget/IntroPreference.kt
@@ -68,6 +68,7 @@
         (holder.findViewById(R.id.collapsable_summary) as? CollapsableTextView)?.apply {
             setCollapsable(isCollapsable)
             setMinLines(minLines)
+            visibility = if (summary.isNullOrEmpty()) View.GONE else View.VISIBLE
             setText(summary.toString())
             if (hyperlinkListener != null) {
                 setHyperlinkListener(hyperlinkListener)