Merge branch 'development' into optimization/unused_files

Signed-off-by: Esteban Papp <81431996+amznestebanpapp@users.noreply.github.com>

# Conflicts:
#	Gems/LmbrCentral/Code/Tests/lmbrcentral_editor_tests_files.cmake

Code/Editor/EditorViewportWidget.cpp

@@ -89,6 +89,7 @@
 #include <LmbrCentral/Rendering/EditorCameraCorrectionBus.h>
 
 // Atom
+#include <Atom/RPI.Public/RenderPipeline.h>
 #include <Atom/RPI.Public/View.h>
 #include <Atom/RPI.Public/ViewportContextManager.h>
 #include <Atom/RPI.Public/ViewProviderBus.h>
@@ -584,7 +585,7 @@ void EditorViewportWidget::OnEditorNotifyEvent(EEditorNotifyEvent event)
         m_renderViewport->SetScene(nullptr);
         break;
 
-    case eNotify_OnEndSceneOpen:
+    case eNotify_OnEndLoad:
         UpdateScene();
         SetDefaultCamera();
         break;
@@ -2324,7 +2325,26 @@ void EditorViewportWidget::UpdateScene()
         {
             AZ::RPI::SceneNotificationBus::Handler::BusDisconnect();
             m_renderViewport->SetScene(mainScene);
-            AZ::RPI::SceneNotificationBus::Handler::BusConnect(m_renderViewport->GetViewportContext()->GetRenderScene()->GetId());
+            auto viewportContext = m_renderViewport->GetViewportContext();
+            AZ::RPI::SceneNotificationBus::Handler::BusConnect(viewportContext->GetRenderScene()->GetId());
+
+            // Don't enable the render pipeline until a level has been loaded
+            // Also show/hide the RenderViewportWidget accordingly so that we get the
+            // expected gradient background when no level is loaded
+            auto renderPipeline = viewportContext->GetCurrentPipeline();
+            if (renderPipeline)
+            {
+                if (GetIEditor()->IsLevelLoaded())
+                {
+                    m_renderViewport->show();
+                    renderPipeline->AddToRenderTick();
+                }
+                else
+                {
+                    m_renderViewport->hide();
+                    renderPipeline->RemoveFromRenderTick();
+                }
+            }
         }
     }
 }

Code/Editor/TrackView/TrackViewDialog.cpp

@@ -1046,7 +1046,12 @@ void CTrackViewDialog::OnAddSequence()
             AzToolsFramework::ScopedUndoBatch undoBatch("Create TrackView Director Node");
             sequenceManager->CreateSequence(sequenceName, sequenceType);
             CTrackViewSequence* newSequence = sequenceManager->GetSequenceByName(sequenceName);
-            AZ_Assert(newSequence, "Creating new sequence failed.");
+
+            if (!newSequence)
+            {
+                return;
+            }
+            
             undoBatch.MarkEntityDirty(newSequence->GetSequenceComponentEntityId());
 
             // make it the currently selected sequence