Open OPML import form.
function openImportForm() {
db_delete('aggregator_category')
->execute();
$category = $this
->randomName(10);
$cid = db_insert('aggregator_category')
->fields(array(
'title' => $category,
'description' => '',
))
->execute();
$this
->drupalGet('admin/config/services/aggregator/add/opml');
$this
->assertText('A single OPML document may contain a collection of many feeds.', 'Found OPML help text.');
$this
->assertField('files[upload]', 'Found file upload field.');
$this
->assertField('remote', 'Found Remote URL field.');
$this
->assertField('refresh', '', 'Found Refresh field.');
$this
->assertFieldByName("category[{$cid}]", $cid, 'Found category field.');
}