Switch does not append its state text to accessibility node infos.

1. Switch was not populating the state on/off test in accessibility
   node infos. It apparently has two texts, the state one and the
   one it inherits from TextView.

bug:6213278

Change-Id: I9c6b1798a8b3230cfb6755cc5b088c320d991642

Author: sganov

core/java/android/widget/Switch.java

@@ -806,5 +806,16 @@ public void onInitializeAccessibilityEvent(AccessibilityEvent event) {
     public void onInitializeAccessibilityNodeInfo(AccessibilityNodeInfo info) {
         super.onInitializeAccessibilityNodeInfo(info);
         info.setClassName(Switch.class.getName());
+        CharSequence switchText = isChecked() ? mTextOn : mTextOff;
+        if (!TextUtils.isEmpty(switchText)) {
+            CharSequence oldText = info.getText();
+            if (TextUtils.isEmpty(oldText)) {
+                info.setText(switchText);
+            } else {
+                StringBuilder newText = new StringBuilder();
+                newText.append(oldText).append(' ').append(switchText);
+                info.setText(newText);
+            }
+        }
     }
 }