Ensure characterBidiLevels get cleared

In TextBoundsInfo#Builder, the clear method was not resetting the value
for the mCharacterBidiLevels property.

Test: atest android.view.inputmethod.cts.TextBoundsInfoTest#testBuilder_characterBidiLevel_isCleared
Bug: 278845496
Change-Id: Ie82780bb0692963d0f0b0123a7169660e591f5a1

core/java/android/view/inputmethod/TextBoundsInfo.java

@@ -1025,6 +1025,7 @@ public final class TextBoundsInfo implements Parcelable {
             mEnd = -1;
             mCharacterBounds = null;
             mCharacterFlags = null;
+            mCharacterBidiLevels = null;
             mLineSegmentFinder = null;
             mWordSegmentFinder = null;
             mGraphemeSegmentFinder = null;