Removed slice based context menu options from the RPE when prefabs are enabled.

Signed-off-by: Chris Galvan <chgalvan@amazon.com>

Code/Framework/AzToolsFramework/AzToolsFramework/UI/PropertyEditor/EntityPropertyEditor.cpp

@@ -1951,12 +1951,13 @@ namespace AzToolsFramework
             return;
         }
 
+        // If prefabs are enabled, there will be no root slice so bail out here since we don't need
+        // to show any slice options in the menu
         AZ::SliceComponent* rootSlice = nullptr;
         AzFramework::SliceEntityOwnershipServiceRequestBus::EventResult(rootSlice, contextId,
             &AzFramework::SliceEntityOwnershipServiceRequestBus::Events::GetRootSlice);
         if (!rootSlice)
         {
-            AZ_Error("PropertyEditor", false, "Entity context has no root slice");
             return;
         }
 
@@ -2105,10 +2106,6 @@ namespace AzToolsFramework
     {
         QMenu* revertMenu = nullptr;
 
-        revertMenu = menu.addMenu(tr("Revert overrides"));
-        revertMenu->setToolTipsVisible(true);
-        revertMenu->setEnabled(false);
-
         //check for changes on selected property
         if (componentClassData)
         {
@@ -2128,6 +2125,11 @@ namespace AzToolsFramework
                 return;
             }
 
+            // Only add the "Revert overrides" menu option if it belongs to a slice
+            revertMenu = menu.addMenu(tr("Revert overrides"));
+            revertMenu->setToolTipsVisible(true);
+            revertMenu->setEnabled(false);
+
             if (fieldNode)
             {
                 bool hasChanges = fieldNode->HasChangesVersusComparison(false);