SL-18721 Window shutdown adjustments

On viewer shutdown
1. Instead of handling potential WM_* messages viewer is no longer
equiped to handle drop window's pointer and expect only WM_DESTROY
2. Detach thread and let it do its own thing, thread will delete itself
3. Reverts commit 1161262029f9619fb02d81575382b64d82d9cd09

Reason for the change: window was closing too early (as son as "LLApp"
status changes) without proper cleanup

1 files changed, 1 insertions, 1 deletions

diff --git a/indra/llcommon/threadpool.h b/indra/llcommon/threadpool.h
index 74056aea17..b8be7bb81a 100644
--- a/indra/llcommon/threadpool.h
+++ b/indra/llcommon/threadpool.h
@@ -55,7 +55,7 @@ namespace LL
          * ThreadPool listens for application shutdown messages on the "LLApp"
          * LLEventPump. Call close() to shut down this ThreadPool early.
          */
-        virtual void close();
+        void close();
 
         std::string getName() const { return mName; }
         size_t getWidth() const { return mThreads.size(); }