Remove const from `const int loops`.

bench/PremulAndUnpremulAlphaOpsBench.cpp

Index: bench/PremulAndUnpremulAlphaOpsBench.cpp
diff --git a/bench/PremulAndUnpremulAlphaOpsBench.cpp b/bench/PremulAndUnpremulAlphaOpsBench.cpp
index a325332de25622dd1a32ac0826e4cb00e8660cf5..a6b7a8c055df1fa581f48e5c4cd85e0fa2502704 100644
--- a/bench/PremulAndUnpremulAlphaOpsBench.cpp
+++ b/bench/PremulAndUnpremulAlphaOpsBench.cpp
@@ -43,7 +43,7 @@ protected:
         fBmp2.allocPixels(info);    // used in readPixels()
     }
 
-    void onDraw(const int loops, SkCanvas* canvas) override {
+    void onDraw(int loops, SkCanvas* canvas) override {
         canvas->clear(SK_ColorBLACK);
 
         for (int loop = 0; loop < loops; ++loop) {