Remove const from `const int loops`.

This drives me nuts, and prevents `while (loops --> 0)`.

BUG=skia:

Review URL: https://codereview.chromium.org/1379923005
diff --git a/bench/RecordingBench.h b/bench/RecordingBench.h
index 6cb5d51..0a8befe 100644
--- a/bench/RecordingBench.h
+++ b/bench/RecordingBench.h
@@ -18,7 +18,7 @@
 protected:
     const char* onGetName() override;
     bool isSuitableFor(Backend) override;
-    void onDraw(const int loops, SkCanvas*) override;
+    void onDraw(int loops, SkCanvas*) override;
     SkIPoint onGetSize() override;
 
 private: