gltfio: improve performance by assuming assets are well-formed.

glTF assets are required to provide min/max attributes for POSITION,
so in theory we never need to compute the AABB. However the option is
still there.

This PR also makes it so that Java clients can choose this option,
previously it was hardcoded for all non-native clients.

android/gltfio-android/src/main/cpp/ResourceLoader.cpp

@@ -35,9 +35,10 @@ static void destroy(void*, size_t, void *userData) {
 
 extern "C" JNIEXPORT jlong JNICALL
 Java_com_google_android_filament_gltfio_ResourceLoader_nCreateResourceLoader(JNIEnv*, jclass,
-        jlong nativeEngine) {
+        jlong nativeEngine, jboolean normalizeSkinningWeights, jboolean recomputeBoundingBoxes) {
     Engine* engine = (Engine*) nativeEngine;
-    return (jlong) new ResourceLoader({ engine, {}, true, true });
+    return (jlong) new ResourceLoader({ engine, {}, (bool) normalizeSkinningWeights,
+            (bool) recomputeBoundingBoxes });
 }
 
 extern "C" JNIEXPORT void JNICALL