Adds content description to the overflow bubble.

Flag: LEGACY persist.wm.debug.bubble_bar DISABLED
Bug: 273994695
Test: SystemUIMicrobenchmark:android.platform.test.scenario.sysui.bubble.BubbleBarTest

Change-Id: Ie3fe451c69a39560aa91a6dfd4d615f172cf3299
diff --git a/quickstep/src/com/android/launcher3/taskbar/bubbles/BubbleView.java b/quickstep/src/com/android/launcher3/taskbar/bubbles/BubbleView.java
index 12cb8c5..6549ad6 100644
--- a/quickstep/src/com/android/launcher3/taskbar/bubbles/BubbleView.java
+++ b/quickstep/src/com/android/launcher3/taskbar/bubbles/BubbleView.java
@@ -163,6 +163,7 @@
         mBubble = overflow;
         mBubbleIcon.setImageBitmap(bitmap);
         mAppIcon.setVisibility(GONE); // Overflow doesn't show the app badge
+        setContentDescription(getResources().getString(R.string.bubble_bar_overflow_description));
     }
 
     /** Returns the bubble being rendered in this view. */
diff --git a/res/values/strings.xml b/res/values/strings.xml
index 4e865d0..f08f8f0 100644
--- a/res/values/strings.xml
+++ b/res/values/strings.xml
@@ -456,4 +456,8 @@
 
     <!-- Private space label -->
     <string name="private_space_label">Private space</string>
+
+    <!-- Strings for bubble bar -->
+    <!-- content description for the overflow bubble [CHAR_LIMIT=none] -->
+    <string name="bubble_bar_overflow_description">Overflow</string>
 </resources>