Simplify benchmark internal API.

I'm not quite sure why I wrote such a convoluted API with setLoops()/getLoops().
This replaces it with a loops argument passed to onDraw().

This CL is largely mechanical translation from the old API to the new one.
MathBench used this->getLoops() outside onDraw(), which seems incorrect.  I
fixed it.

BUG=
R=djsollen@google.com

Author: mtklein@google.com

Review URL: https://codereview.chromium.org/99893003

git-svn-id: http://skia.googlecode.com/svn/trunk@12466 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/bench/ChartBench.cpp b/bench/ChartBench.cpp
index ceb62b4..47fe752 100644
--- a/bench/ChartBench.cpp
+++ b/bench/ChartBench.cpp
@@ -102,7 +102,7 @@
         }
     }
 
-    virtual void onDraw(SkCanvas* canvas) SK_OVERRIDE {
+    virtual void onDraw(const int loops, SkCanvas* canvas) SK_OVERRIDE {
         bool sizeChanged = false;
         if (canvas->getDeviceSize() != fSize) {
             fSize = canvas->getDeviceSize();
@@ -122,7 +122,7 @@
             }
         }
 
-        for (int frame = 0; frame < this->getLoops(); ++frame) {
+        for (int frame = 0; frame < loops; ++frame) {
 
             canvas->clear(0xFFE0F0E0);