lib/private/Files/Type/Detection.php
/**
	 * Add an extension -> mimetype mapping
	 *
	 * $mimetype is the assumed correct mime type
	 * The optional $secureMimeType is an alternative to send to send
	 * to avoid potential XSS.
	 *
	 * @param string $extension
	 * @param string $mimetype
	 * @param string|null $secureMimeType
	 */
Add an extension -> mimetype mapping
$mimetype is the assumed correct mime type
The optional $secureMimeType is an alternative to send to send
to avoid potential XSS.

@param string $extension
@param string $mimetype
@param string|null $secureMimeType
Add an extension - > mimetype mapping $mimetype is the assumed correct mime type The optional $secureMimeType is an alternative to send to send to avoid potential XSS . @param string $extension @param string $mimetype @param string|null $secureMimeType
public function registerType($extension,
								 $mimetype,
								 $secureMimeType = null) {
		$this->mimetypes[$extension] = array($mimetype, $secureMimeType);
		$this->secureMimeTypes[$mimetype] = $secureMimeType ?: $mimetype;
	}
public function registerType ( $ extension , $ mimetype , $ secureMimeType = null ) { $ this -> mimetypes [ $ extension ] = array ( $ mimetype , $ secureMimeType ) ; $ this -> secureMimeTypes [ $ mimetype ] = $ secureMimeType ? : $ mimetype ; }
Add an extension -> mimetype mapping
 $mimetype is the assumed correct mime type
 The optional $secureMimeType is an alternative to send to send
 to avoid potential XSS.
Add an extension - > mimetype mapping $mimetype is the assumed correct mime type The optional $secureMimeType is an alternative to send to send to avoid potential XSS .