add grapheneos.version system feature

This allows to add OS-version-specific packages to the GrapheneOS App Store.

Author: muhomorr

services/core/java/com/android/server/SystemConfig.java

@@ -1820,6 +1820,15 @@ private void readAllPermissionsFromEnvironment() {
 
         addFeature("grapheneos.package_update_preserves_package_enabled_setting", 0);
         addFeature("grapheneos.priv_installer_can_use_getSharedLibraries_MATCH_ANY_USER", 0);
+
+        try {
+            int version = Integer.parseInt(Build.VERSION.INCREMENTAL);
+            if (version > 0) {
+                addFeature("grapheneos.version", version);
+            }
+        } catch (NumberFormatException e) {
+            Slog.w(TAG, "unable to parse Build.VERSION.INCREMENTAL", e);
+        }
     }
 
     private @Nullable SignedPackage parseEnhancedConfirmationTrustedPackage(XmlPullParser parser,