Don't enable a11y service if scary dialog obscured

Bug: 38134845
Test: Trivial back-port of ag/2066325; relying on treehugger
Change-Id: I784eebebe45847431e67aa9032f2f1367156a440
diff --git a/src/com/android/settings/accessibility/ToggleAccessibilityServicePreferenceFragment.java b/src/com/android/settings/accessibility/ToggleAccessibilityServicePreferenceFragment.java
index 16389cb..5be0bec 100644
--- a/src/com/android/settings/accessibility/ToggleAccessibilityServicePreferenceFragment.java
+++ b/src/com/android/settings/accessibility/ToggleAccessibilityServicePreferenceFragment.java
@@ -196,7 +196,7 @@
                     @Override
                     public boolean onTouch(View v, MotionEvent event) {
                         // Filter obscured touches by consuming them.
-                        if ((event.getFlags() & MotionEvent.FLAG_WINDOW_IS_OBSCURED) != 0) {
+                        if ((event.getFlags() & MotionEvent.FLAG_WINDOW_IS_PARTIALLY_OBSCURED) != 0) {
                             if (event.getAction() == MotionEvent.ACTION_UP) {
                                 Toast.makeText(v.getContext(), R.string.touch_filtered_warning,
                                         Toast.LENGTH_SHORT).show();