docs: public T get(GVRAndroidResource androidResource) {
          WeakReference<T> reference = cache.get(androidResource);
          if (reference == null) {
              // Not in map
              // Log.d(TAG, "get(%s) returning %s", androidResource, null);
              return null;
          }
          T cached = reference.get();
          if (cached == null) {
              // In map, but not in memory
              cache.remove(androidResource);
          } else {
              // No one will ever read this stream
              androidResource.closeStream();
          }
          // Log.d(TAG, "get(%s) returning %s", androidResource, cached);
          return cached;
      }