Define a protobuf format for representing plots. Add code to convert the C-representation generated by the RtcEventLog analysis tool, to the new protobuf format.

BUG=webrtc:6249

NOTRY=True

Review-Url: https://codereview.webrtc.org/2268063002
Cr-Commit-Position: refs/heads/master@{#13873}

webrtc/tools/event_log_visualizer/plot_protobuf.h

@@ -0,0 +1,39 @@
+/*
+ *  Copyright (c) 2016 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+#ifndef WEBRTC_TOOLS_EVENT_LOG_VISUALIZER_PLOT_PROTOBUF_H_
+#define WEBRTC_TOOLS_EVENT_LOG_VISUALIZER_PLOT_PROTOBUF_H_
+
+#include "webrtc/tools/event_log_visualizer/graph.pb.h"
+#include "webrtc/tools/event_log_visualizer/plot_base.h"
+
+namespace webrtc {
+namespace plotting {
+
+class ProtobufPlot final : public Plot {
+ public:
+  ProtobufPlot();
+  ~ProtobufPlot() override;
+  void Draw() override;
+  void ExportProtobuf(protobuf_plot::Plot* plot);
+};
+
+class ProtobufPlotCollection final : public PlotCollection {
+ public:
+  ProtobufPlotCollection();
+  ~ProtobufPlotCollection() override;
+  void Draw() override;
+  Plot* AppendNewPlot() override;
+  void ExportProtobuf(protobuf_plot::PlotCollection* collection);
+};
+
+}  // namespace plotting
+}  // namespace webrtc
+
+#endif  // WEBRTC_TOOLS_EVENT_LOG_VISUALIZER_PLOT_PROTOBUF_H_