Remove mixins storage as they are now handled in the formatter

Author: kylekatarnls

src/Phug/Compiler.php

@@ -71,7 +71,6 @@
 use Phug\Parser\Node\YieldNode;
 use Phug\Parser\NodeInterface;
 // Utils
-use Phug\Util\AssociativeStorage;
 use Phug\Util\ModuleContainerInterface;
 use Phug\Util\Partial\ModuleContainerTrait;
 use Phug\Util\SourceLocation;
@@ -126,11 +125,6 @@ class Compiler implements ModuleContainerInterface, CompilerInterface
      */
     private $layout;
 
-    /**
-     * @var AssociativeStorage
-     */
-    private $mixins;
-
     /**
      * @var NodeInterface
      */
@@ -161,7 +155,6 @@ public function __construct($options = null)
             'parser_class_name'    => Parser::class,
             'formatter_class_name' => Formatter::class,
             'locator_class_name'   => FileLocator::class,
-            'mixins_storage_mode'  => AssociativeStorage::REPLACE,
             'compiler_modules'     => [],
             'node_compilers'       => [
                 AssignmentListNode::class  => AssignmentListNodeCompiler::class,
@@ -229,11 +222,6 @@ public function __construct($options = null)
             $this->setNodeCompiler($className, $handler);
         }
 
-        $this->mixins = new AssociativeStorage(
-            'mixin',
-            $this->getOption('mixins_storage_mode')
-        );
-
         if ($onCompile = $this->getOption('on_compile')) {
             $this->attach(CompilerEvent::COMPILE, $onCompile);
         }