TextView should report in an AccessibilityNodeInfo's text its hint if the View text is empty.

1. TextView was reporting only its text as the text of the emmited AccessibilityNodeInfo
   not using the hint if the text is empty which is inconsistent with the handling of
   accessibility events.

2. TextView was using the contentDescription in AccessibilityEvents if its
   text and hint are empyty. However, the content description is reported as
   a separate event property and it is incorrect to report it as the text.

bug:5129138

Change-Id: I1c9270459cb07650a0ec5181cc4a01993dde3b5c

Author: sganov

core/java/android/widget/TextView.java

@@ -8939,14 +8939,8 @@ public void onPopulateAccessibilityEvent(AccessibilityEvent event) {
 
         final boolean isPassword = hasPasswordTransformationMethod();
         if (!isPassword) {
-            CharSequence text = getText();
+            CharSequence text = getTextForAccessibility();
             if (TextUtils.isEmpty(text)) {
-                text = getHint();
-            }
-            if (TextUtils.isEmpty(text)) {
-                text = getContentDescription();
-            }
-            if (!TextUtils.isEmpty(text)) {
                 event.getText().add(text);
             }
         }
@@ -8972,7 +8966,7 @@ public void onInitializeAccessibilityNodeInfo(AccessibilityNodeInfo info) {
 
         final boolean isPassword = hasPasswordTransformationMethod();
         if (!isPassword) {
-            info.setText(getText());
+            info.setText(getTextForAccessibility());
         }
         info.setPassword(isPassword);
     }
@@ -8988,6 +8982,20 @@ public void sendAccessibilityEvent(int eventType) {
         super.sendAccessibilityEvent(eventType);
     }
 
+    /**
+     * Gets the text reported for accessibility purposes. It is the
+     * text if not empty or the hint.
+     *
+     * @return The accessibility text.
+     */
+    private CharSequence getTextForAccessibility() {
+        CharSequence text = getText();
+        if (TextUtils.isEmpty(text)) {
+            text = getHint();
+        }
+        return text;
+    }
+
     void sendAccessibilityEventTypeViewTextChanged(CharSequence beforeText,
             int fromIndex, int removedCount, int addedCount) {
         AccessibilityEvent event =