Update to Drupal 8.1.2. For more information, see https://www.drupal.org/project/drupal/releases/8.1.2

core/lib/Drupal/Core/Cache/BackendChain.php

@@ -19,7 +19,6 @@ namespace Drupal\Core\Cache;
  *
  * @ingroup cache
  */
-
 class BackendChain implements CacheBackendInterface, CacheTagsInvalidatorInterface {
 
   /**

core/lib/Drupal/Core/Cache/Cache.php

@@ -76,10 +76,10 @@ class Cache {
    */
   public static function mergeMaxAges($a = Cache::PERMANENT, $b = Cache::PERMANENT) {
     // If one of the values is Cache::PERMANENT, return the other value.
-    if ($a === Cache::PERMANENT){
+    if ($a === Cache::PERMANENT) {
       return $b;
     }
-    if ($b === Cache::PERMANENT){
+    if ($b === Cache::PERMANENT) {
       return $a;
     }
 

core/lib/Drupal/Core/Cache/CacheBackendInterface.php

@@ -215,4 +215,5 @@ interface CacheBackendInterface {
    * Remove a cache bin.
    */
   public function removeBin();
+
 }

core/lib/Drupal/Core/Cache/CacheTagsChecksumInterface.php

@@ -54,4 +54,5 @@ interface CacheTagsChecksumInterface {
    * This is only used by tests.
    */
   public function reset();
+
 }

core/lib/Drupal/Core/Cache/CacheableMetadata.php

@@ -6,7 +6,6 @@ namespace Drupal\Core\Cache;
  * Defines a generic class for passing cacheability metadata.
  *
  * @ingroup cache
- *
  */
 class CacheableMetadata implements RefinableCacheableDependencyInterface {
 

core/lib/Drupal/Core/Cache/Context/CacheContextsManager.php

@@ -98,7 +98,6 @@ class CacheContextsManager {
    * @return \Drupal\Core\Cache\Context\ContextCacheKeys
    *   The ContextCacheKeys object containing the converted cache keys and
    *   cacheability metadata.
-   *
    */
   public function convertTokensToKeys(array $context_tokens) {
     assert('$this->assertValidTokens($context_tokens)');
@@ -195,7 +194,7 @@ class CacheContextsManager {
             $ancestor_found = TRUE;
           }
 
-        } while(!$ancestor_found && strpos($ancestor, '.') !== FALSE);
+        } while (!$ancestor_found && strpos($ancestor, '.') !== FALSE);
         if (!$ancestor_found) {
           $optimized_content_tokens[] = $context_token;
         }

core/lib/Drupal/Core/Cache/Context/LanguagesCacheContext.php

@@ -8,7 +8,7 @@ use Drupal\Core\Language\LanguageManagerInterface;
 /**
  * Defines the LanguagesCacheContext service, for "per language" caching.
  */
-class LanguagesCacheContext implements CalculatedCacheContextInterface  {
+class LanguagesCacheContext implements CalculatedCacheContextInterface {
 
   /**
    * The language manager.

core/lib/Drupal/Core/Cache/Context/QueryArgsCacheContext.php

@@ -27,8 +27,17 @@ class QueryArgsCacheContext extends RequestStackCacheContextBase implements Calc
     if ($query_arg === NULL) {
       return $this->requestStack->getCurrentRequest()->getQueryString();
     }
+    elseif ($this->requestStack->getCurrentRequest()->query->has($query_arg)) {
+      $value = $this->requestStack->getCurrentRequest()->query->get($query_arg);
+      if ($value !== '') {
+        return $value;
+      }
+      else {
+        return '?valueless?';
+      }
+    }
     else {
-      return $this->requestStack->getCurrentRequest()->query->get($query_arg);
+      return NULL;
     }
   }
 

core/lib/Drupal/Core/Cache/DatabaseBackend.php

@@ -477,4 +477,5 @@ class DatabaseBackend implements CacheBackendInterface {
     );
     return $schema;
   }
+
 }

core/lib/Drupal/Core/Cache/ListCacheBinsPass.php

@@ -28,4 +28,5 @@ class ListCacheBinsPass implements CompilerPassInterface {
     $container->setParameter('cache_bins', $cache_bins);
     $container->setParameter('cache_default_bin_backends', $cache_default_bin_backends);
   }
+
 }

core/lib/Drupal/Core/Cache/MemoryCounterBackend.php

@@ -9,7 +9,6 @@ namespace Drupal\Core\Cache;
  * many times a cache entry was set or requested.
  *
  * @todo On the longrun this backend should be replaced by phpunit mock objects.
- *
  */
 class MemoryCounterBackend extends MemoryBackend {
 
@@ -49,7 +48,6 @@ class MemoryCounterBackend extends MemoryBackend {
    *
    * @param string $function
    *   The called function.
-   *
    * @param string $cid
    *   The cache ID of the cache entry to increase the counter.
    */

core/lib/Drupal/Core/Cache/NullBackend.php

@@ -88,4 +88,5 @@ class NullBackend implements CacheBackendInterface {
    * {@inheritdoc}
    */
   public function removeBin() {}
+
 }

core/lib/Drupal/Core/Cache/PhpBackend.php

@@ -211,7 +211,7 @@ class PhpBackend implements CacheBackendInterface {
    * {@inheritdoc}
    */
   public function invalidateAll() {
-    foreach($this->storage()->listAll() as $cidhash) {
+    foreach ($this->storage()->listAll() as $cidhash) {
       $this->invalidatebyHash($cidhash);
     }
   }