Text::tokenize don't tokenize correctly when specified multi-byte character as separator

[tt512]

I used Text::tokenize to tokenize by multi-byte character such as double width whitespace.
But It don't tokenize correctly.

I added test case to end of TextTest::testTokenize and the test become failure.

diff --git a/tests/TestCase/Utility/TextTest.php b/tests/TestCase/Utility/TextTest.php
index 1df51bf..cd58880 100644
--- a/tests/TestCase/Utility/TextTest.php
+++ b/tests/TestCase/Utility/TextTest.php
@@ -315,6 +315,10 @@ class TextTest extends TestCase
         $result = Text::tokenize('tagA "single tag" tagB', ' ', '"', '"');
         $expected = ['tagA', '"single tag"', 'tagB'];
         $this->assertEquals($expected, $result);
+
+        $result = Text::tokenize('tagA　"single　tag"　tagB', '　', '"', '"');
+        $expected = ['tagA', '"single　tag"', 'tagB'];
+        $this->assertEquals($expected, $result);
     }

     public function testReplaceWithQuestionMarkInString()

 phpunit tests/TestCase/Utility/TextTest.php 
PHPUnit 4.7.6 by Sebastian Bergmann and contributors.

.....F...........................................

Time: 275 ms, Memory: 17.25Mb

There was 1 failure:

1) Cake\Test\TestCase\Utility\TextTest::testTokenize
Failed asserting that two arrays are equal.
--- Expected
+++ Actual
@@ @@
 Array (
-    0 => 'tagA'
-    1 => '"single　tag"'
-    2 => 'tagB'
+    0 => 'tagA　"single　tag"　tagB'
 )

/tmp/workspace/tests/TestCase/Utility/TextTest.php:321

FAILURES!
Tests: 49, Assertions: 735, Failures: 1.

[markstory]

Pull request open now.