Invalidate TextView on change of elegantTextHeight

Previously we were setting the paint but not invalidating, so it
could show stale content.

Bug: 27572149
Change-Id: I668667ec5b95a96e31a58cff0f8bbbb9958e470c
diff --git a/core/java/android/widget/TextView.java b/core/java/android/widget/TextView.java
index ac3eaf7..4c461ad 100644
--- a/core/java/android/widget/TextView.java
+++ b/core/java/android/widget/TextView.java
@@ -3071,7 +3071,14 @@
      * @attr ref android.R.styleable#TextView_elegantTextHeight
      */
     public void setElegantTextHeight(boolean elegant) {
-        mTextPaint.setElegantTextHeight(elegant);
+        if (elegant != mTextPaint.isElegantTextHeight()) {
+            mTextPaint.setElegantTextHeight(elegant);
+            if (mLayout != null) {
+                nullLayouts();
+                requestLayout();
+                invalidate();
+            }
+        }
     }
 
     /**