Add scrollable text to biometric prompt

Test: Verified the marquee text scrolls if text is too large to display
on a single line.
Bug: 201045056

Change-Id: I7af434295fa90b9229e10a124b97c7f4588fb7c5

packages/SystemUI/res/layout/auth_biometric_contents.xml

@@ -73,6 +73,9 @@
         android:accessibilityLiveRegion="polite"
         android:singleLine="true"
         android:ellipsize="marquee"
+        android:marqueeRepeatLimit="marquee_forever"
+        android:scrollHorizontally="true"
+        android:fadingEdge="horizontal"
         android:textColor="@color/biometric_dialog_gray"/>
 
     <LinearLayout

packages/SystemUI/src/com/android/systemui/biometrics/AuthBiometricView.java

@@ -636,6 +636,7 @@ public abstract class AuthBiometricView extends LinearLayout {
         mIndicatorView.setText(message);
         mIndicatorView.setTextColor(mTextColorError);
         mIndicatorView.setVisibility(View.VISIBLE);
+        mIndicatorView.setSelected(true);
         mHandler.postDelayed(resetMessageRunnable, mInjector.getDelayAfterError());
 
         Utils.notifyAccessibilityContentChanged(mAccessibilityManager, this);