SL-10702: When attempting a new voice connection, ensure that the voicePump mail drop does not have any outstanding events.

indra/llcommon/llevents.h

@@ -582,11 +582,12 @@ public:
     /// Generate a distinct name for a listener -- see listen()
     static std::string inventName(const std::string& pfx="listener");
 
-private:
-    friend class LLEventPumps;
     /// flush queued events
     virtual void flush() {}
 
+private:
+    friend class LLEventPumps;
+
     virtual void reset();
 
 
@@ -675,8 +676,10 @@ public:
     virtual ~LLEventMailDrop() {}
     
     /// Post an event to all listeners
-    virtual bool post(const LLSD& event);
+    virtual bool post(const LLSD& event) override;
     
+    /// Remove any history stored in the mail drop.
+    virtual void flush() override { mEventHistory.clear(); LLEventStream::flush(); };
 protected:
     virtual LLBoundListener listen_impl(const std::string& name, const LLEventListener&,
                                         const NameList& after,
@@ -703,7 +706,6 @@ public:
     /// Post an event to all listeners
     virtual bool post(const LLSD& event);
 
-private:
     /// flush queued events
     virtual void flush();
 

indra/newview/llvoicevivox.cpp

@@ -1591,6 +1591,11 @@ bool LLVivoxVoiceClient::addAndJoinSession(const sessionStatePtr_t &nextSession)
 
     LLSD timeoutResult(LLSDMap("session", "timeout"));
 
+    // We are about to start a whole new session.  Anything that MIGHT still be in our 
+    // maildrop is going to be stale and cause us much wailing and gnashing of teeth.  
+    // Just flush it all out and start new.
+    voicePump.flush();
+
     // It appears that I need to wait for BOTH the SessionGroup.AddSession response and the SessionStateChangeEvent with state 4
     // before continuing from this state.  They can happen in either order, and if I don't wait for both, things can get stuck.
     // For now, the SessionGroup.AddSession response handler sets mSessionHandle and the SessionStateChangeEvent handler transitions to stateSessionJoined.