Use direct reference to enum in AaptAssets

The second argument to the getNavHiddenName can be NULL, so use a direct
reference to the class to get the enum values instead of the argument.

Change-Id: I0444572c23cb4de9e7da15a8310a49cf4619bb15
diff --git a/tools/aapt/AaptAssets.cpp b/tools/aapt/AaptAssets.cpp
index dc442aa..69b2207 100644
--- a/tools/aapt/AaptAssets.cpp
+++ b/tools/aapt/AaptAssets.cpp
@@ -985,14 +985,14 @@
     uint8_t mask = 0;
     uint8_t value = 0;
     if (strcmp(name, kWildcardName) == 0) {
-        mask = out->MASK_NAVHIDDEN;
-        value = out->NAVHIDDEN_ANY;
+        mask = ResTable_config::MASK_NAVHIDDEN;
+        value = ResTable_config::NAVHIDDEN_ANY;
     } else if (strcmp(name, "navexposed") == 0) {
-        mask = out->MASK_NAVHIDDEN;
-        value = out->NAVHIDDEN_NO;
+        mask = ResTable_config::MASK_NAVHIDDEN;
+        value = ResTable_config::NAVHIDDEN_NO;
     } else if (strcmp(name, "navhidden") == 0) {
-        mask = out->MASK_NAVHIDDEN;
-        value = out->NAVHIDDEN_YES;
+        mask = ResTable_config::MASK_NAVHIDDEN;
+        value = ResTable_config::NAVHIDDEN_YES;
     }
 
     if (mask != 0) {