Add a warmup flag to visualbench

tools/VisualBench/VisualBenchmarkStream.cpp

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  *
  */
 
 #include <VisualBench/VisualBenchmarkStream.h>
 #include <VisualBench/WrappedBenchmark.h>
@@ skipping 13 matching lines @@
 DEFINE_string2(match, m, nullptr,
                "[~][^]substring[$] [...] of bench name to run.\n"
                "Multiple matches may be separated by spaces.\n"
                "~ causes a matching bench to always be skipped\n"
                "^ requires the start of the bench to match\n"
                "$ requires the end of the bench to match\n"
                "^ and $ requires an exact match\n"
                "If a bench does not match any list entry,\n"
                "it is skipped unless some list entry starts with ~");
 DEFINE_string(skps, "skps", "Directory to read skps from.");
+DEFINE_bool(warmup, true, "Include a warmup bench? (Excluding the warmup may compromise results)");
 
 // We draw a big nonAA path to warmup the gpu / cpu
 #include "SkPerlinNoiseShader.h"
 class WarmupBench : public Benchmark {
 public:
     WarmupBench() {
         sk_tool_utils::make_big_path(fPath);
         fPerlinRect = SkRect::MakeLTRB(0., 0., 400., 400.);
     }
 private:
@@ skipping 75 matching lines @@
     pic->reset(SkPicture::CreateFromStream(stream.get()));
     if (pic->get() == nullptr) {
         SkDebugf("Could not read %s as an SkPicture.\n", path);
         return false;
     }
     return true;
 }
 
 Benchmark* VisualBenchmarkStream::next() {
     Benchmark* bench;
-    if (!fIsWarmedUp) {
+    if (FLAGS_warmup && !fIsWarmedUp) {
         fIsWarmedUp = true;
         bench = new WarmupBench;
     } else {
         // skips non matching benches
         while ((bench = this->innerNext()) &&
                (SkCommandLineFlags::ShouldSkip(FLAGS_match, bench->getUniqueName()) ||
                 !bench->isSuitableFor(Benchmark::kGPU_Backend))) {
             bench->unref();
         }
     }
@@ skipping 40 matching lines @@
         }
 
         SkString name = SkOSPath::Basename(path.c_str());
         fSourceType = "skp";
         fBenchType = "playback";
         return new VisualSKPBench(name.c_str(), pic.get());
     }
 
     return nullptr;
 }