Fix DocumentTest/SkDocument memory leaks

https://codereview.chromium.org/72833002/



git-svn-id: http://skia.googlecode.com/svn/trunk@12302 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/tests/DocumentTest.cpp b/tests/DocumentTest.cpp
index 1838687..a717ac7 100644
--- a/tests/DocumentTest.cpp
+++ b/tests/DocumentTest.cpp
@@ -9,7 +9,7 @@
 static void test_empty(skiatest::Reporter* reporter) {
     SkDynamicMemoryWStream stream;
 
-    SkDocument* doc = SkDocument::CreatePDF(&stream);
+    SkAutoTUnref<SkDocument> doc(SkDocument::CreatePDF(&stream));
 
     doc->close();