Fix unused var warning-as-error



git-svn-id: http://skia.googlecode.com/svn/trunk@7513 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/samplecode/SampleManyRects.cpp b/samplecode/SampleManyRects.cpp
index 04d8a41..d5d71f4 100644
--- a/samplecode/SampleManyRects.cpp
+++ b/samplecode/SampleManyRects.cpp
@@ -36,8 +36,6 @@
 
     virtual void onDrawContent(SkCanvas* canvas) {
         SkISize dsize = canvas->getDeviceSize();
-        SkRect canvasRect = SkRect::MakeWH(SkIntToScalar(dsize.fWidth),
-                                           SkIntToScalar(dsize.fHeight));
         canvas->clear(0xFFF0E0F0);
 
         for (int i = 0; i < N; ++i) {