Telemetry / Devtools TraceHandler: exposes tracing via dev tools.

content/browser/debugger/devtools_browser_target.h

Index: content/browser/debugger/devtools_browser_target.h
diff --git a/content/browser/debugger/devtools_browser_target.h b/content/browser/debugger/devtools_browser_target.h
new file mode 100644
index 0000000000000000000000000000000000000000..14e141fe4e8fd30d93d05178149f73c9dc2b8880
--- /dev/null
+++ b/content/browser/debugger/devtools_browser_target.h
@@ -0,0 +1,68 @@
+// Copyright (c) 2012 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_BROWSER_DEBUGGER_DEVTOOLS_BROWSER_TARGET_H_
+#define CONTENT_BROWSER_DEBUGGER_DEVTOOLS_BROWSER_TARGET_H_
+
+#include <map>
+#include <string>
+
+#include "base/basictypes.h"
+
+namespace base {
+
+class DictionaryValue;
+class Value;
+
+}  // namespace base
+
+namespace content {
+
+// This class handles the "Browser" target for remote debugging.
+class DevToolsBrowserTarget {
+ public:
+  class Handler {
+   public:
+    virtual ~Handler() {}
+
+    // Returns the domain name for this handler.
+    virtual std::string Domain() = 0;
+
+    // |return_value| and |error_message_out| ownership is transferred to the
+    // caller.
+    virtual base::Value* OnProtocolCommand(
+        const std::string& method,
+        const base::DictionaryValue* params,
+        base::Value** error_message_out) = 0;
+  };
+
+  explicit DevToolsBrowserTarget(int connection_id);
+  ~DevToolsBrowserTarget();
+
+  int connection_id() const { return connection_id_; }
+
+  // Takes ownership of |handler|.
+  void RegisterHandler(Handler* handler);
+
+  std::string HandleMessage(const std::string& data);
+
+ private:
+  const int connection_id_;
+
+  typedef std::map<std::string, Handler*> HandlersMap;
+  HandlersMap handlers_;
+
+  // Takes ownership of |error_object|.
+  std::string SerializeErrorResponse(int request_id, base::Value* error_object);
+
+  base::Value* CreateErrorObject(int error_code, const std::string& message);
+
+  std::string SerializeResponse(int request_id, base::Value* response);
+
+  DISALLOW_COPY_AND_ASSIGN(DevToolsBrowserTarget);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_BROWSER_DEBUGGER_DEVTOOLS_BROWSER_TARGET_H_