Inspector: replace generic discardAgents logic with explicit call to discard a listener.

Source/core/inspector/InspectorDOMDebuggerAgent.cpp

Index: Source/core/inspector/InspectorDOMDebuggerAgent.cpp
diff --git a/Source/core/inspector/InspectorDOMDebuggerAgent.cpp b/Source/core/inspector/InspectorDOMDebuggerAgent.cpp
index 3bbc1cbd9165cb6421aabc082946c6530a11e065..074ffd052a08f2323860468c0b9c44e822741f7c 100644
--- a/Source/core/inspector/InspectorDOMDebuggerAgent.cpp
+++ b/Source/core/inspector/InspectorDOMDebuggerAgent.cpp
@@ -90,7 +90,8 @@ InspectorDOMDebuggerAgent::InspectorDOMDebuggerAgent(InstrumentingAgents* instru
 
 InspectorDOMDebuggerAgent::~InspectorDOMDebuggerAgent()
 {
-    ASSERT(!m_debuggerAgent);
+    if (m_debuggerAgent)
+        m_debuggerAgent->setListener(0);
     ASSERT(!m_instrumentingAgents->inspectorDOMDebuggerAgent());
 }
 
@@ -115,6 +116,11 @@ void InspectorDOMDebuggerAgent::didPause()
     m_pauseInNextEventListener = false;
 }
 
+void InspectorDOMDebuggerAgent::discardListener()
+{
+    m_debuggerAgent = 0;
+}
+
 void InspectorDOMDebuggerAgent::didProcessTask()
 {
     if (!m_pauseInNextEventListener)
@@ -135,12 +141,6 @@ void InspectorDOMDebuggerAgent::clearFrontend()
     disable();
 }
 
-void InspectorDOMDebuggerAgent::discardAgent()
-{
-    m_debuggerAgent->setListener(0);
-    m_debuggerAgent = 0;
-}
-
 void InspectorDOMDebuggerAgent::discardBindings()
 {
     m_domBreakpoints.clear();