make SkDeviceFactory reference counted



git-svn-id: http://skia.googlecode.com/svn/trunk@1180 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/pdf/SkPDFDevice.cpp b/src/pdf/SkPDFDevice.cpp
index efe7257..13ffd5b 100644
--- a/src/pdf/SkPDFDevice.cpp
+++ b/src/pdf/SkPDFDevice.cpp
@@ -168,6 +168,10 @@
     }
 }
 
+SkDeviceFactory* SkPDFDevice::onNewDeviceFactory() {
+    return SkNEW(SkPDFDeviceFactory);
+}
+
 void SkPDFDevice::cleanUp() {
     fGraphicStateResources.unrefAll();
     fXObjectResources.unrefAll();