Updating Symfony lib and dependencies:

Package operations: 2 installs, 23 updates, 0 removals
  - Updating psr/log (1.1.0 => 1.1.2)
  - Updating symfony/debug (v3.4.30 => v3.4.35)
  - Updating symfony/console (v3.4.30 => v3.4.35)
  - Updating symfony/dotenv (v3.4.30 => v3.4.35)
  - Updating symfony/routing (v3.4.30 => v3.4.35)
  - Updating symfony/finder (v3.4.30 => v3.4.35)
  - Updating symfony/filesystem (v3.4.30 => v3.4.35)
  - Installing symfony/polyfill-util (v1.12.0)
  - Installing symfony/polyfill-php56 (v1.12.0)
  - Updating symfony/http-foundation (v3.4.30 => v3.4.35)
  - Updating symfony/event-dispatcher (v3.4.30 => v3.4.35)
  - Updating symfony/http-kernel (v3.4.30 => v3.4.35)
  - Updating symfony/config (v3.4.30 => v3.4.35)
  - Updating symfony/dependency-injection (v3.4.30 => v3.4.35)
  - Updating symfony/class-loader (v3.4.30 => v3.4.35)
  - Updating symfony/cache (v3.4.30 => v3.4.35)
  - Updating symfony/framework-bundle (v3.4.30 => v3.4.35)
  - Updating twig/twig (v1.42.2 => v1.42.4)
  - Updating symfony/twig-bridge (v3.4.30 => v3.4.35)
  - Updating symfony/twig-bundle (v3.4.30 => v3.4.35)
  - Updating symfony/yaml (v3.4.30 => v3.4.35)
  - Updating symfony/stopwatch (v3.4.30 => v3.4.35)
  - Updating symfony/var-dumper (v3.4.30 => v3.4.35)
  - Updating symfony/web-profiler-bundle (v3.4.30 => v3.4.35)
  - Updating symfony/css-selector (v3.4.30 => v3.4.35)

lib/symfony/http-kernel/HttpCache/AbstractSurrogate.php

@@ -109,6 +109,8 @@ abstract class AbstractSurrogate implements SurrogateInterface
                 throw $e;
             }
         }
+
+        return '';
     }
 
     /**

lib/symfony/http-kernel/HttpCache/Esi.php

@@ -111,5 +111,7 @@ class Esi extends AbstractSurrogate
 
         // remove ESI/1.0 from the Surrogate-Control header
         $this->removeFromControl($response);
+
+        return $response;
     }
 }

lib/symfony/http-kernel/HttpCache/HttpCache.php

@@ -432,9 +432,8 @@ class HttpCache implements HttpKernelInterface, TerminableInterface
      * All backend requests (cache passes, fetches, cache validations)
      * run through this method.
      *
-     * @param Request  $request A Request instance
-     * @param bool     $catch   Whether to catch exceptions or not
-     * @param Response $entry   A Response instance (the stale entry if present, null otherwise)
+     * @param bool          $catch Whether to catch exceptions or not
+     * @param Response|null $entry A Response instance (the stale entry if present, null otherwise)
      *
      * @return Response A Response instance
      */
@@ -646,8 +645,6 @@ class HttpCache implements HttpKernelInterface, TerminableInterface
     /**
      * Calculates the key we use in the "trace" array for a given request.
      *
-     * @param Request $request
-     *
      * @return string
      */
     private function getTraceKey(Request $request)
@@ -664,8 +661,6 @@ class HttpCache implements HttpKernelInterface, TerminableInterface
      * Checks whether the given (cached) response may be served as "stale" when a revalidation
      * is currently in progress.
      *
-     * @param Response $entry
-     *
      * @return bool true when the stale response may be served, false otherwise
      */
     private function mayServeStaleWhileRevalidate(Response $entry)

lib/symfony/http-kernel/HttpCache/ResponseCacheStrategy.php

@@ -130,7 +130,6 @@ class ResponseCacheStrategy implements ResponseCacheStrategyInterface
         $response->headers->set('Cache-Control', implode(', ', array_keys($flags)));
 
         $maxAge = null;
-        $sMaxage = null;
 
         if (is_numeric($this->ageDirectives['max-age'])) {
             $maxAge = $this->ageDirectives['max-age'] + $this->age;

lib/symfony/http-kernel/HttpCache/Ssi.php

@@ -94,5 +94,7 @@ class Ssi extends AbstractSurrogate
 
         // remove SSI/1.0 from the Surrogate-Control header
         $this->removeFromControl($response);
+
+        return $response;
     }
 }

lib/symfony/http-kernel/HttpCache/Store.php

@@ -134,7 +134,7 @@ class Store implements StoreInterface
         $key = $this->getCacheKey($request);
 
         if (!$entries = $this->getMetadata($key)) {
-            return;
+            return null;
         }
 
         // find a cached entry that matches the request.
@@ -148,7 +148,7 @@ class Store implements StoreInterface
         }
 
         if (null === $match) {
-            return;
+            return null;
         }
 
         $headers = $match[1];
@@ -159,6 +159,7 @@ class Store implements StoreInterface
         // TODO the metaStore referenced an entity that doesn't exist in
         // the entityStore. We definitely want to return nil but we should
         // also purge the entry from the meta-store when this is detected.
+        return null;
     }
 
     /**
@@ -180,7 +181,7 @@ class Store implements StoreInterface
         if (!$response->headers->has('X-Content-Digest')) {
             $digest = $this->generateContentDigest($response);
 
-            if (false === $this->save($digest, $response->getContent())) {
+            if (!$this->save($digest, $response->getContent())) {
                 throw new \RuntimeException('Unable to store the entity.');
             }
 
@@ -209,7 +210,7 @@ class Store implements StoreInterface
 
         array_unshift($entries, [$storedEnv, $headers]);
 
-        if (false === $this->save($key, serialize($entries))) {
+        if (!$this->save($key, serialize($entries))) {
             throw new \RuntimeException('Unable to store the metadata.');
         }
 
@@ -248,7 +249,7 @@ class Store implements StoreInterface
             }
         }
 
-        if ($modified && false === $this->save($key, serialize($entries))) {
+        if ($modified && !$this->save($key, serialize($entries))) {
             throw new \RuntimeException('Unable to store the metadata.');
         }
     }
@@ -349,13 +350,13 @@ class Store implements StoreInterface
      *
      * @param string $key The store key
      *
-     * @return string The data associated with the key
+     * @return string|null The data associated with the key
      */
     private function load($key)
     {
         $path = $this->getPath($key);
 
-        return file_exists($path) ? file_get_contents($path) : false;
+        return file_exists($path) && false !== ($contents = file_get_contents($path)) ? $contents : null;
     }
 
     /**
@@ -408,6 +409,8 @@ class Store implements StoreInterface
         }
 
         @chmod($path, 0666 & ~umask());
+
+        return true;
     }
 
     public function getPath($key)