Allow printing graphs as protobuf in event_log_visualizer.

event_log_visualizer --protobuf_output <file>
will print a binary protobuf description of the graphs.

Also piggy-backing a couple of trivial spelling fixes in the same CL.

Bug: None
Change-Id: Ib000aa2706de51659ee72f13b773c4394edafe3e
Reviewed-on: https://webrtc-review.googlesource.com/99320
Reviewed-by: Elad Alon <eladalon@webrtc.org>
Commit-Queue: Björn Terelius <terelius@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#24675}
diff --git a/rtc_tools/event_log_visualizer/plot_protobuf.cc b/rtc_tools/event_log_visualizer/plot_protobuf.cc
index 0c4c709..54975e1 100644
--- a/rtc_tools/event_log_visualizer/plot_protobuf.cc
+++ b/rtc_tools/event_log_visualizer/plot_protobuf.cc
@@ -61,7 +61,11 @@
 
 ProtobufPlotCollection::~ProtobufPlotCollection() {}
 
-void ProtobufPlotCollection::Draw() {}
+void ProtobufPlotCollection::Draw() {
+  webrtc::analytics::ChartCollection collection;
+  ExportProtobuf(&collection);
+  std::cout << collection.SerializeAsString();
+}
 
 void ProtobufPlotCollection::ExportProtobuf(
     webrtc::analytics::ChartCollection* collection) {