Create VisualStreamTimingModule

BUG=skia:

Review URL: https://codereview.chromium.org/1385073002
diff --git a/tools/VisualBench/VisualStreamTimingModule.h b/tools/VisualBench/VisualStreamTimingModule.h
new file mode 100644
index 0000000..ac06ed4
--- /dev/null
+++ b/tools/VisualBench/VisualStreamTimingModule.h
@@ -0,0 +1,48 @@
+/*
+ * Copyright 2015 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef VisualStreamTimingModule_DEFINED
+#define VisualStreamTimingModule_DEFINED
+
+#include "VisualModule.h"
+
+#include "TimingStateMachine.h"
+#include "VisualBench.h"
+#include "VisualBenchmarkStream.h"
+
+/*
+ * VisualStreamTimingModule is the base class for modules which want to time a stream of Benchmarks.
+ *
+ * Subclasses should implement renderFrame, which is called for each frame, and timingFinished,
+ * which is called when a sample has finished timing.
+ */
+class VisualStreamTimingModule : public VisualModule {
+public:
+    VisualStreamTimingModule(VisualBench* owner, bool preWarmBeforeSample);
+    void draw(SkCanvas* canvas) override;
+
+private:
+    virtual void renderFrame(SkCanvas*, Benchmark*, int loops)=0;
+
+    // subclasses should return true to advance the stream
+    virtual bool timingFinished(Benchmark*, int loops, double measurement)=0;
+
+    bool nextBenchmarkIfNecessary(SkCanvas*);
+
+    TimingStateMachine fTSM;
+    SkAutoTDelete<VisualBenchmarkStream> fBenchmarkStream;
+    SkAutoTUnref<Benchmark> fBenchmark;
+    bool fReinitializeBenchmark;
+    bool fPreWarmBeforeSample;
+
+    // support framework
+    VisualBench* fOwner;
+
+    typedef VisualModule INHERITED;
+};
+
+#endif