Fixing NoGPU build of bench
Problem was: As of r4989, SkDeferredCanvas.h no longer includes SkDevice.h

Unreviewed

git-svn-id: http://skia.googlecode.com/svn/trunk@4993 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/bench/benchmain.cpp b/bench/benchmain.cpp
index 9bf1776..7cfa849 100644
--- a/bench/benchmain.cpp
+++ b/bench/benchmain.cpp
@@ -24,6 +24,7 @@
 #include "SkBenchmark.h"
 #include "SkCanvas.h"
 #include "SkDeferredCanvas.h"
+#include "SkDevice.h"
 #include "SkColorPriv.h"
 #include "SkGraphics.h"
 #include "SkImageEncoder.h"