Guard against SecurityException of accessing to slice uri

- Sometimes unregistering a Slice callback will have no permission to
unpin the Slice uri and throw an exception.
- Guard against the exception as the first solution.

Bug: 159722324
Test: robotest
Change-Id: Ic227331fef64c3fa6fe3e4442fba2a9b754d520d
diff --git a/src/com/android/settings/homepage/contextualcards/EligibleCardChecker.java b/src/com/android/settings/homepage/contextualcards/EligibleCardChecker.java
index 46b4c86..f98d795 100644
--- a/src/com/android/settings/homepage/contextualcards/EligibleCardChecker.java
+++ b/src/com/android/settings/homepage/contextualcards/EligibleCardChecker.java
@@ -120,9 +120,13 @@
 
         // Workaround of unpinning slice in the same SerialExecutor of AsyncTask as SliceCallback's
         // observer.
-        ThreadUtils.postOnMainThread(() ->
-                AsyncTask.execute(() -> manager.unregisterSliceCallback(uri, callback))
-        );
+        ThreadUtils.postOnMainThread(() -> AsyncTask.execute(() -> {
+            try {
+                manager.unregisterSliceCallback(uri, callback);
+            } catch (SecurityException e) {
+                Log.d(TAG, "No permission currently: " + e);
+            }
+        }));
 
         return slice;
     }