[DevTools] Rework DevToolsSession interaction with domain handlers.

content/browser/devtools/protocol/system_info_handler.h

Index: content/browser/devtools/protocol/system_info_handler.h
diff --git a/content/browser/devtools/protocol/system_info_handler.h b/content/browser/devtools/protocol/system_info_handler.h
index 2abbd5913b7eadffcf93d77330df0e1232c7b8b5..dbb64ae22ef6b2b8ee033295f2a75b7eded7801d 100644
--- a/content/browser/devtools/protocol/system_info_handler.h
+++ b/content/browser/devtools/protocol/system_info_handler.h
@@ -8,6 +8,7 @@
 #include <set>
 
 #include "base/macros.h"
+#include "content/browser/devtools/protocol/devtools_domain_handler.h"
 #include "content/browser/devtools/protocol/system_info.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/gpu_data_manager_observer.h"
@@ -15,14 +16,14 @@
 namespace content {
 namespace protocol {
 
-class SystemInfoHandler : public SystemInfo::Backend {
+class SystemInfoHandler : public DevToolsDomainHandler,
+                          public SystemInfo::Backend {
  public:
 
   SystemInfoHandler();
   ~SystemInfoHandler() override;
 
-  void Wire(UberDispatcher*);
-  Response Disable() override;
+  void Wire(UberDispatcher* dispatcher) override;
 
   void GetInfo(std::unique_ptr<GetInfoCallback> callback) override;