Re-land first pass BackgroundTracingManager.

content/public/browser/background_tracing_config.h

+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CONTENT_PUBLIC_BROWSER_BACKGROUND_TRACING_CONFIG_H_
+#define CONTENT_PUBLIC_BROWSER_BACKGROUND_TRACING_CONFIG_H_
+
+#include "base/trace_event/trace_event_impl.h"
+#include "content/common/content_export.h"
+
+namespace base {
+class DictionaryValue;
+}
+
+namespace content {
+
+// BackgroundTracingConfig is passed to the BackgroundTracingManager to
+// setup the trigger rules used to enable/disable background tracing.
+struct CONTENT_EXPORT BackgroundTracingConfig {
+  virtual ~BackgroundTracingConfig();
+
+  enum Mode {
+    PREEMPTIVE_TRACING_MODE,
+    REACTIVE_TRACING_MODE,
+  };
+  enum CategoryPreset {
+    BENCHMARK,
+    BENCHMARK_DEEP,
+  };
+
+  Mode mode;
+
+  static BackgroundTracingConfig* FromDict(const base::DictionaryValue* dict);
+  static void IntoDict(const BackgroundTracingConfig* config,

[nduca, 2015/05/21 20:02:55]

drive by: bit puzzled why this is pass-in instead of returns scoped ptr...

[nduca, 2015/05/21 20:04:51]

and, also puzzled why its static. 

seems like we should have

virtual void scoped_ptr<DValue> AsDict() = 0;


then the base has a private member [nonstatic] called IntoDict.

+                       base::DictionaryValue* dict);
+
+ protected:
+  BackgroundTracingConfig(Mode mode);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_PUBLIC_BROWSER_BACKGROUND_TRACING_CONFIG_H_