Revert of DevTools: use per-LocalFrame instrumenting agents instead of per-Page ones.

Source/core/inspector/InspectorTracingAgent.h

 /*
  * Copyright 2014 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 InspectorTracingAgent_h
 #define InspectorTracingAgent_h
 
 #include "core/InspectorFrontend.h"
 #include "core/inspector/InspectorBaseAgent.h"
 #include "wtf/PassOwnPtr.h"
 #include "wtf/text/WTFString.h"
 
 namespace blink {
 
 class InspectorClient;
-class InspectorPageAgent;
 class InspectorWorkerAgent;
+class Page;
 
 class InspectorTracingAgent final
     : public InspectorBaseAgent<InspectorTracingAgent>
     , public InspectorBackendDispatcher::TracingCommandHandler {
     WTF_MAKE_NONCOPYABLE(InspectorTracingAgent);
 public:
-    static PassOwnPtrWillBeRawPtr<InspectorTracingAgent> create(InspectorClient* client, InspectorWorkerAgent* workerAgent, InspectorPageAgent* pageAgent)
+    static PassOwnPtrWillBeRawPtr<InspectorTracingAgent> create(InspectorClient* client, InspectorWorkerAgent* workerAgent, Page* page)
     {
-        return adoptPtrWillBeNoop(new InspectorTracingAgent(client, workerAgent, pageAgent));
+        return adoptPtrWillBeNoop(new InspectorTracingAgent(client, workerAgent, page));
     }
 
     void trace(Visitor*) override;
 
     // Base agent methods.
     virtual void restore() override;
     virtual void setFrontend(InspectorFrontend*) override;
     virtual void clearFrontend() override;
 
     // Protocol method implementations.
     virtual void start(ErrorString*, const String* categoryFilter, const String*, const double*, PassRefPtrWillBeRawPtr<StartCallback>) override;
     virtual void end(ErrorString*, PassRefPtrWillBeRawPtr<EndCallback>);
 
     // Methods for other agents to use.
     void setLayerTreeId(int);
 
 private:
-    InspectorTracingAgent(InspectorClient*, InspectorWorkerAgent*, InspectorPageAgent*);
+    InspectorTracingAgent(InspectorClient*, InspectorWorkerAgent*, Page*);
 
     void emitMetadataEvents();
     void resetSessionId();
     String sessionId();
 
     int m_layerTreeId;
     InspectorClient* m_client;
     InspectorFrontend::Tracing* m_frontend;
     RawPtrWillBeMember<InspectorWorkerAgent> m_workerAgent;
-    RawPtrWillBeMember<InspectorPageAgent> m_pageAgent;
+    RawPtrWillBeMember<Page> m_page;
 };
 
 } // namespace blink
 
 #endif // InspectorTracingAgent_h