fix(class): add interface

Closes #3403522

src/Scanner.php

@@ -13,7 +13,7 @@ use Drupal\clamav\Config;
  * Passes the methods "scan" and "version" to a specific handler, according to
  * the configuration.
  */
-class Scanner {
+class Scanner implements ScannerInterface {
 
   // Constants defining the infection state of a specific file.
   const FILE_IS_UNCHECKED = -1;
@@ -139,21 +139,8 @@ class Scanner {
     return $scannable;
   }
 
-
   /**
-   * Scan a file for viruses.
-   *
-   * @param Drupal\file\FileInterface $file
-   *   The file to scan for viruses.
-   *
-   * @return int
-   *   One of the following class constants:
-   *   - CLAMAV_SCANRESULT_UNCHECKED
-   *     The file was not scanned. The ClamAV service may be unavailable.
-   *   - CLAMAV_SCANRESULT_CLEAN
-   *     The file was scanned, and no infection was found.
-   *   - CLAMAV_SCANRESULT_INFECTED
-   *     The file was scanned, and found to be infected with a virus.
+   * {@inheritdoc}
    */
   public function scan(FileInterface $file) {
     // Empty files are never infected.
@@ -201,10 +188,7 @@ class Scanner {
   }
 
   /**
-   * The version of the ClamAV service.
-   *
-   * @return string
-   *   The version number provided by ClamAV.
+   * {@inheritdoc}
    */
   public function version() {
     return $this->scanner->version();