Fixed an accessibility issue with the pin view

We were sending an accessibility event even if there were no
characters left, leading to an additional "bullet deleted"
notice.

Test: input pin, delte pins one bye one, observe no talkback spoken anymore at the end
Bug: 62714260
Change-Id: Iee751e31f702f4b0dc6d5a15d31d58e71bfa797e
(cherry picked from commit 8a72b06a26718cb8bdfd2ad6ae31623b60911f39)
diff --git a/packages/SystemUI/src/com/android/keyguard/PasswordTextView.java b/packages/SystemUI/src/com/android/keyguard/PasswordTextView.java
index c43820d..f5c82a7 100644
--- a/packages/SystemUI/src/com/android/keyguard/PasswordTextView.java
+++ b/packages/SystemUI/src/com/android/keyguard/PasswordTextView.java
@@ -28,10 +28,8 @@
 import android.graphics.Typeface;
 import android.os.PowerManager;
 import android.os.SystemClock;
-import android.os.UserHandle;
 import android.provider.Settings;
 import android.text.InputType;
-import android.text.TextUtils;
 import android.util.AttributeSet;
 import android.view.Gravity;
 import android.view.View;
@@ -248,9 +246,9 @@
             mText = mText.substring(0, length - 1);
             CharState charState = mTextChars.get(length - 1);
             charState.startRemoveAnimation(0, 0);
+            sendAccessibilityEventTypeViewTextChanged(textbefore, textbefore.length() - 1, 1, 0);
         }
         userActivity();
-        sendAccessibilityEventTypeViewTextChanged(textbefore, textbefore.length() - 1, 1, 0);
     }
 
     public String getText() {