Fixing deadlock related to thumbnails

Adding smoothing to thumbnails in AssetBrowser

Code/Framework/AzToolsFramework/AzToolsFramework/Thumbnails/Thumbnail.cpp

@@ -10,12 +10,14 @@
 *
 */
 
+#include <AzToolsFramework/Thumbnails/ThumbnailerBus.h>
 #include <AzToolsFramework/Thumbnails/Thumbnail.h>
 AZ_PUSH_DISABLE_WARNING(4127 4251 4800 4244, "-Wunknown-warning-option") // 4127: conditional expression is constant
                                                                          // 4251: 'QTextCodec::ConverterState::flags': class 'QFlags<QTextCodec::ConversionFlag>' needs to have dll-interface to be used by clients of struct 'QTextCodec::ConverterState'
                                                                          // 4800: 'QTextBoundaryFinderPrivate *const ': forcing value to bool 'true' or 'false' (performance warning)
                                                                          // 4244: conversion from 'int' to 'qint8', possible loss of data
 #include <QtConcurrent/QtConcurrent>
+#include <QThreadPool>
 AZ_POP_DISABLE_WARNING
 
 namespace AzToolsFramework
@@ -80,7 +82,11 @@ namespace AzToolsFramework
             if (m_state == State::Unloaded)
             {
                 m_state = State::Loading;
-                QFuture<void> future = QtConcurrent::run([this](){ LoadThread(); });
+                QThreadPool* threadPool;
+                ThumbnailContextRequestBus::BroadcastResult(
+                    threadPool,
+                    &ThumbnailContextRequestBus::Handler::GetThreadPool);
+                QFuture<void> future = QtConcurrent::run(threadPool, [this](){ LoadThread(); });
                 m_watcher.setFuture(future);
             }
         }