Extract debugger target enumeration into a separate class

content/public/browser/devtools_agent_host.h

Index: content/public/browser/devtools_agent_host.h
diff --git a/content/public/browser/devtools_agent_host.h b/content/public/browser/devtools_agent_host.h
index 533c31df79f1545ef84ab2f450590b77339aa4a0..8395b2d8f25075f75f9a0bc9333e698f69527651 100644
--- a/content/public/browser/devtools_agent_host.h
+++ b/content/public/browser/devtools_agent_host.h
@@ -6,6 +6,7 @@
 #define CONTENT_PUBLIC_BROWSER_DEVTOOLS_AGENT_HOST_H_
 
 #include <string>
+#include <vector>
 
 #include "base/basictypes.h"
 #include "base/memory/ref_counted.h"
@@ -35,16 +36,22 @@ class CONTENT_EXPORT DevToolsAgentHost
 
   static bool IsDebuggerAttached(WebContents* web_contents);
 
-  // Detaches given |rvh| from the agent host temporarily and returns a cookie
-  // that allows to reattach another rvh to that agen thost later. Returns -1 if
-  // there is no agent host associated with the |rvh|.
-  static int DisconnectRenderViewHost(RenderViewHost* rvh);
+  // Detaches given |rvh| from the agent host temporarily and returns the agent
+  // host id that allows to reattach another rvh to that agent host later.
+  // Returns empty string if there is no agent host associated with the |rvh|.
+  static std::string DisconnectRenderViewHost(RenderViewHost* rvh);
 
   // Reattaches agent host detached with DisconnectRenderViewHost method above
   // to |rvh|.
-  static void ConnectRenderViewHost(int agent_host_cookie,
+  static void ConnectRenderViewHost(const std::string& agent_host_cookie,
                                     RenderViewHost* rvh);
 
+  // Returns a list of all existing RenderViewHost's that can be debugged.
+  static std::vector<RenderViewHost*> GetValidRenderViewHosts();
+
+  // Returns the unique id of the agent.
+  virtual std::string GetId() = 0;
+
   // Returns render view host instance for this host if any.
   virtual RenderViewHost* GetRenderViewHost() = 0;