Fix memory corruption in test

Bug: 18012918
Change-Id: I8d69624e9be9f0399ddba10ce3903f93177d5930
diff --git a/libs/hwui/tests/main.cpp b/libs/hwui/tests/main.cpp
index 3e9a86f..e796e79 100644
--- a/libs/hwui/tests/main.cpp
+++ b/libs/hwui/tests/main.cpp
@@ -76,6 +76,7 @@
     sp<Surface> surface = control->getSurface();
 
     RenderNode* rootNode = new RenderNode();
+    rootNode->incStrong(0);
     rootNode->mutateStagingProperties().setLeftTopRightBottom(0, 0, width, height);
     rootNode->setPropertyFieldsDirty(RenderNode::X | RenderNode::Y);
     rootNode->mutateStagingProperties().setClipToBounds(false);