frameworks\base\core\java\android\app\usage\StorageStatsManager.java
限制:调用 StorageStatsManager 获取EMMC才可生效
public @BytesLong long getTotalBytes(@NonNull UUID storageUuid) throws IOException {
++ // try {`在这里插入代码片`
++ // return mService.getTotalBytes(convert(storageUuid), mContext.getOpPackageName());
++ long total = 17179869184L;
++ return total;
++ // } catch (ParcelableException e) {
++ // e.maybeRethrow(IOException.class);
++ // throw new RuntimeException(e);
++ // } catch (RemoteException e) {
++ // throw e.rethrowFromSystemServer();
++ // }
}