Add warning for a known issue in a newly added API

checkUriPermissions is a new API added in Android S to check multiple
uri permissions via single API call.
However, checkUriPermissions is not working as intended for secondary
users. The root cause has been found and the fix is merged for later
releases.

Bug: 194700183
Test: atest --user-type secondary_user CtsScopedStorageDeviceOnlyTest:android.scopedstorage.cts.device.RedactUriDeviceTest#testSharedRedactedUri_openFileForRead
Change-Id: I72db7f0b4ddf97dce14880b6341799106d711c5c

core/java/android/content/Context.java

@@ -5935,6 +5935,10 @@ public abstract class Context {
      * more general access to the URI's content provider then this check will
      * always fail.
      *
+     * <strong>Note:</strong> On SDK Version {@link android.os.Build.VERSION_CODES#S},
+     * calling this method from a secondary-user's context will incorrectly return
+     * {@link PackageManager#PERMISSION_DENIED} for all {code uris}.
+     *
      * @param uris The list of URIs that is being checked.
      * @param pid The process ID being checked against.  Must be &gt; 0.
      * @param uid The user ID being checked against.  A uid of 0 is the root