[android] use AAssetManager instead of libzip

test/api/custom_layer.test.cpp

@@ -89,14 +89,7 @@ TEST(CustomLayer, Basic) {
     HeadlessBackend backend { test::sharedDisplay() };
     BackendScope scope { backend };
     OffscreenView view { backend.getContext() };
-
-#ifdef MBGL_ASSET_ZIP
-    // Regenerate with `cd test/fixtures/api/ && zip -r assets.zip assets/`
-    DefaultFileSource fileSource(":memory:", "test/fixtures/api/assets.zip");
-#else
     DefaultFileSource fileSource(":memory:", "test/fixtures/api/assets");
-#endif
-
     ThreadPool threadPool(4);
 
     Map map(backend, view.getSize(), 1, fileSource, threadPool, MapMode::Still);