We should draw at least once for benchmark

Bug: skia:6792
Change-Id: Ia69c7601abead8f30963de709f22e27e04798319
Reviewed-on: https://skia-review.googlesource.com/20697
Reviewed-by: Mike Reed <reed@google.com>
Commit-Queue: Yuqian Li <liyuqian@google.com>
diff --git a/bench/PathBench.cpp b/bench/PathBench.cpp
index 6991db5..757ffcc 100644
--- a/bench/PathBench.cpp
+++ b/bench/PathBench.cpp
@@ -68,7 +68,7 @@
         }
         count >>= (3 * complexity());
 
-        for (int i = 0; i < count; i++) {
+        for (int i = 0; i < SkTMax(1, count); i++) {
             canvas->drawPath(path, paint);
         }
     }
@@ -1082,7 +1082,7 @@
 public:
     TightBoundsBench(SkRect (*proc)(const SkPath&), const char suffix[]) : fProc(proc) {
         fName.printf("tight_bounds_%s", suffix);
-        
+
         const int N = 100;
         SkRandom rand;
         for (int i = 0; i < N; ++i) {
@@ -1102,13 +1102,13 @@
     }
 
     const char* onGetName() override { return fName.c_str(); }
-    
+
     void onDraw(int loops, SkCanvas* canvas) override {
         for (int i = 0; i < loops*100; ++i) {
             fProc(fPath);
         }
     }
-    
+
 private:
     typedef Benchmark INHERITED;
 };