protected function getDefaultFacets() {
		$availableFacets = $this->getAvailableFacets();
		return array_combine(array_keys($availableFacets), array_fill(0, count($availableFacets), array()));
	}
protected function getDefaultFacets() {
		$availableFacets = $this->getAvailableFacets();
		return array_combine(array_keys($availableFacets), array_fill(0, count($availableFacets), array()));
	}
Returns an array of preselected facets (no facet selected is the default)

@return string[string][]