Re-land first pass BackgroundTracingManager.

content/public/browser/background_tracing_reactive_config.h

Index: content/public/browser/background_tracing_reactive_config.h
diff --git a/content/public/browser/background_tracing_reactive_config.h b/content/public/browser/background_tracing_reactive_config.h
new file mode 100644
index 0000000000000000000000000000000000000000..d0979577f7b91df8a8ee2da97d1ccee9c8d2c1c0
--- /dev/null
+++ b/content/public/browser/background_tracing_reactive_config.h
@@ -0,0 +1,35 @@
+// 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_REACTIVE_CONFIG_H_
+#define CONTENT_PUBLIC_BROWSER_BACKGROUND_TRACING_REACTIVE_CONFIG_H_
+
+#include "content/public/browser/background_tracing_config.h"
+
+namespace content {
+
+// BackgroundTracingReactiveConfig holds trigger rules for use during
+// reactive tracing. Tracing will be not be enabled immediately, rather
+// the BackgroundTracingManager will wait for a trigger to occur, and
+// enable tracing at that point. Tracing will be finalized later, either
+// after some time has elapsed or the trigger occurs again.
+struct CONTENT_EXPORT BackgroundTracingReactiveConfig
+    : public BackgroundTracingConfig {
+ public:
+  BackgroundTracingReactiveConfig();
+  ~BackgroundTracingReactiveConfig() override;
+
+  enum RuleType { TRACE_ON_MANUAL_TRIGGER_UNTIL_10S_OR_NEXT_TRIGGER_OR_FULL };
+  struct TracingRule {
+    RuleType type;
+    std::string trigger_name;
+    CategoryPreset category_preset;
+  };
+
+  std::vector<TracingRule> configs;
+};
+
+}  // namespace content
+
+#endif  // CONTENT_PUBLIC_BROWSER_BACKGROUND_TRACING_REACTIVE_CONFIG_H_