added m_drawContextRegistered flag to stop error calling UnregisterDynamicDrawContext in AtomViewportDisplayIconsSystemComponent

Signed-off-by: Guthrie Adams <guthadam@amazon.com>

Gems/AtomLyIntegration/AtomViewportDisplayIcons/Code/Source/AtomViewportDisplayIconsSystemComponent.cpp

@@ -82,6 +82,8 @@ namespace AZ::Render
 
     void AtomViewportDisplayIconsSystemComponent::Activate()
     {
+        m_drawContextRegistered = false;
+
         AzToolsFramework::EditorViewportIconDisplay::Register(this);
 
         Bootstrap::NotificationBus::Handler::BusConnect();
@@ -97,9 +99,10 @@ namespace AZ::Render
         {
             return;
         } 
-        if (perViewportDynamicDrawInterface)
+        if (perViewportDynamicDrawInterface && m_drawContextRegistered)
         {
             perViewportDynamicDrawInterface->UnregisterDynamicDrawContext(m_drawContextName);
+            m_drawContextRegistered = false;
         }
 
         AzToolsFramework::EditorViewportIconDisplay::Unregister(this);
@@ -367,6 +370,8 @@ namespace AZ::Render
                 drawContext->EndInit();
             });
 
+        m_drawContextRegistered = true;
+
         Data::AssetBus::Handler::BusDisconnect();
     }
 } // namespace AZ::Render

Gems/AtomLyIntegration/AtomViewportDisplayIcons/Code/Source/AtomViewportDisplayIconsSystemComponent.h

@@ -77,6 +77,8 @@ namespace AZ
             };
             AZStd::unordered_map<IconId, IconData> m_iconData;
             IconId m_currentId = 0;
+
+            bool m_drawContextRegistered = false;
         };
     } // namespace Render
 } // namespace AZ