@Override
    public int delete(Uri uri, String selection, String[] selectionArgs) {
        // ContentProvider has already checked granted permissions
        final File file = mStrategy.getFileForUri(uri);
        return file.delete() ? 1 : 0;
    }
Deletes the file associated with the specified content URI, as
returned by {@link #getUriForFile(Context, String, File) getUriForFile()}. Notice that this
method does <b>not</b> throw an {@link IOException}; you must check its return value.

@param uri           A content URI for a file, as returned by
                     {@link #getUriForFile(Context, String, File) getUriForFile()}.
@param selection     Ignored. Set to {@code null}.
@param selectionArgs Ignored. Set to {@code null}.
@return 1 if the delete succeeds; otherwise, 0.
replugin-sample/host/app/src/main/java/com/qihoo360/replugin/sample/host/FileProvider.java