Just a quick reference post for missing SearchResults.aspx Page Layout in a SharePoint Online Site Collection created using the Enterprise Records Centre template.
When activating the SharePoint Server Publishing Infrastructure Site Collection Feature, we have seen instances of it taking over 40 minutes! The subsequent “SharePoint Server Publishing” Site Feature takes only a minute or two, as would be expected. However, once these Features have been activated, the Search Results Page Layout (part of the Welcome Page Content Type) is missing from the Master Page gallery:
No amount of re-activating the Features deploys the Page Layout. The only solution we have found in this case is to remove the Site Collection and create a new one (see my SharePoint Online – Remove Site Collection from Recycle Bin post for more help).
In some cases, we have seen the Search Results Page Layout deployed with the Features, however the configuration is incorrect. See the example below where the wrong Content Type is selected:
In these instances, updating the properties appears to resolve the problem, but note that we have seen inconsistent behaviour where (for example) sometimes the preview field is missing and others it has automatically updated itself.
I will update the post if we find any more information but for now, it looks like the Enterprise Records Centre template in SharePoint Online is not provisioning quite right.