DevTools: disable DOMDebuggerAgent when DOMAgent or DebuggerAgent were disabled.

Source/core/inspector/InspectorDOMDebuggerAgent.h

Index: Source/core/inspector/InspectorDOMDebuggerAgent.h
diff --git a/Source/core/inspector/InspectorDOMDebuggerAgent.h b/Source/core/inspector/InspectorDOMDebuggerAgent.h
index b38deef0d3f5a3427a9504a37234338029145541..fe2ee7cbc05223667b4217cdc023898c605247b5 100644
--- a/Source/core/inspector/InspectorDOMDebuggerAgent.h
+++ b/Source/core/inspector/InspectorDOMDebuggerAgent.h
@@ -33,6 +33,7 @@
 
 
 #include "core/inspector/InspectorBaseAgent.h"
+#include "core/inspector/InspectorDOMAgent.h"
 #include "core/inspector/InspectorDebuggerAgent.h"
 #include "wtf/HashMap.h"
 #include "wtf/PassOwnPtr.h"
@@ -53,7 +54,11 @@ class Node;
 
 typedef String ErrorString;
 
-class InspectorDOMDebuggerAgent FINAL : public InspectorBaseAgent<InspectorDOMDebuggerAgent>, public InspectorDebuggerAgent::Listener, public InspectorBackendDispatcher::DOMDebuggerCommandHandler {
+class InspectorDOMDebuggerAgent FINAL :
+    public InspectorBaseAgent<InspectorDOMDebuggerAgent>,
+    public InspectorDebuggerAgent::Listener,
+    public InspectorDOMAgent::Listener,
+    public InspectorBackendDispatcher::DOMDebuggerCommandHandler {
     WTF_MAKE_NONCOPYABLE(InspectorDOMDebuggerAgent);
 public:
     static PassOwnPtr<InspectorDOMDebuggerAgent> create(InspectorDOMAgent*, InspectorDebuggerAgent*);
@@ -101,6 +106,10 @@ private:
     void pauseOnNativeEventIfNeeded(PassRefPtr<JSONObject> eventData, bool synchronous);
     PassRefPtr<JSONObject> preparePauseOnNativeEventData(bool isDOMEvent, const String& eventName);
 
+    // InspectorDOMAgent::Listener implementation.
+    virtual void domAgentWasEnabled() OVERRIDE;
+    virtual void domAgentWasDisabled() OVERRIDE;
+
     // InspectorDebuggerAgent::Listener implementation.
     virtual void debuggerWasEnabled() OVERRIDE;
     virtual void debuggerWasDisabled() OVERRIDE;