minor symfony#17378 [Asset] ChooseBaseUrl should return an offset (bburnichon)

This PR was merged into the 2.7 branch.

Discussion
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[Asset] ChooseBaseUrl should return an offset

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets |
| License       | MIT
| Doc PR        |

Enforce chooseBaseUrl to return an integer offset to the baseUrls member.

Commits
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0d041c3 ChooseBaseUrl should return an index

Author: fabpot

src/Symfony/Component/Asset/UrlPackage.php

@@ -108,15 +108,15 @@ public function getBaseUrl($path)
      * Determines which base URL to use for the given path.
      *
      * Override this method to change the default distribution strategy.
-     * This method should always return the same base URL for a given path.
+     * This method should always return the same base URL index for a given path.
      *
      * @param string $path
      *
-     * @return string The base URL for the given path
+     * @return int The base URL index for the given path
      */
     protected function chooseBaseUrl($path)
     {
-        return fmod(hexdec(substr(hash('sha256', $path), 0, 10)), count($this->baseUrls));
+        return (int) fmod(hexdec(substr(hash('sha256', $path), 0, 10)), count($this->baseUrls));
     }
 
     private function getSslUrls($urls)