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.cpp b/bench/RecordingBench.cpp
index c66e11a..1cc4d15 100644
--- a/bench/RecordingBench.cpp
+++ b/bench/RecordingBench.cpp
@@ -28,7 +28,7 @@
                           SkScalarCeilToInt(fSrc->cullRect().height()));
 }
 
-void RecordingBench::onDraw(const int loops, SkCanvas*) {
+void RecordingBench::onDraw(int loops, SkCanvas*) {
     SkRTreeFactory factory;
     const SkScalar w = fSrc->cullRect().width(),
                    h = fSrc->cullRect().height();