Correct argument order for drawSimpleRect()

Patch by Ryan Sleevi <rsleevi@chromium.org>
Review URL: http://codereview.appspot.com/4568055/

git-svn-id: http://skia.googlecode.com/svn/trunk@1523 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/gpu/src/GrGpu.cpp b/gpu/src/GrGpu.cpp
index 4fe7ccc..4f260c7 100644
--- a/gpu/src/GrGpu.cpp
+++ b/gpu/src/GrGpu.cpp
@@ -527,7 +527,7 @@
                         }
                     } else {
                         SET_RANDOM_COLOR
-                        this->drawSimpleRect(bounds, 0, NULL);
+                        this->drawSimpleRect(bounds, NULL, 0);
                     }
                 }
             }