Use IteratorDecorator from core

As far as I can tell, EchoIteratorDecorator is functionally identical to
IteratorDecorator from includes/libs/iterators/ in core, so why have a
separate copy? (EchoIteratorDecorator does pass through the return value
of next() or rewind(), if any, but there shouldn't be any per the
Iterator interface.)

Change-Id: Ic763ec19c15f67d9c9b42ebffb88c52b9056ed22

extension.json

@@ -1106,7 +1106,6 @@
 		"EchoHtmlDigestEmailFormatter": "includes/formatters/EchoHtmlDigestEmailFormatter.php",
 		"EchoHtmlEmailFormatter": "includes/formatters/EchoHtmlEmailFormatter.php",
 		"EchoIcon": "includes/formatters/EchoIcon.php",
-		"EchoIteratorDecorator": "includes/iterator/IteratorDecorator.php",
 		"EchoLocalCache": "includes/cache/LocalCache.php",
 		"EchoMentionInSummaryPresentationModel": "includes/formatters/MentionInSummaryPresentationModel.php",
 		"EchoMentionPresentationModel": "includes/formatters/MentionPresentationModel.php",

includes/iterator/CallbackIterator.php

@@ -3,7 +3,7 @@
 /**
  * Applies a callback to all values returned from the iterator
  */
-class EchoCallbackIterator extends EchoIteratorDecorator {
+class EchoCallbackIterator extends IteratorDecorator {
 	/** @var callable */
 	protected $callable;
 

includes/iterator/IteratorDecorator.php

@@ -1,34 +0,0 @@
-<?php
-
-/**
- * Allows extending classes to decorate an Iterator with
- * reduced boilerplate.
- */
-abstract class EchoIteratorDecorator implements Iterator {
-	/** @var Iterator */
-	protected $iterator;
-
-	public function __construct( Iterator $iterator ) {
-		$this->iterator = $iterator;
-	}
-
-	public function current() {
-		return $this->iterator->current();
-	}
-
-	public function key() {
-		return $this->iterator->key();
-	}
-
-	public function next() {
-		return $this->iterator->next();
-	}
-
-	public function rewind() {
-		return $this->iterator->rewind();
-	}
-
-	public function valid() {
-		return $this->iterator->valid();
-	}
-}

includes/iterator/NotRecursiveIterator.php

@@ -7,7 +7,7 @@
  * Alternatively wraps a recursive iterator to prevent recursing deeper
  * than the wrapped iterator.
  */
-class EchoNotRecursiveIterator extends EchoIteratorDecorator implements RecursiveIterator {
+class EchoNotRecursiveIterator extends IteratorDecorator implements RecursiveIterator {
 	public function hasChildren() {
 		return false;
 	}