Also include user's v1 ID in export requests

services/web/app/coffee/Features/Exports/ExportsHandler.coffee

@@ -31,7 +31,7 @@ module.exports = ExportsHandler = self =
 				ProjectLocator.findRootDoc {project: results.project, project_id: project_id}, cb
 			]
 			user: (cb) ->
-				UserGetter.getUser user_id, {first_name: 1, last_name: 1, email: 1}, cb
+				UserGetter.getUser user_id, {first_name: 1, last_name: 1, email: 1, overleaf: 1}, cb
 			historyVersion: (cb) ->
 				self._requestVersion project_id, cb
 
@@ -63,6 +63,7 @@ module.exports = ExportsHandler = self =
 					lastName: user.last_name
 					email: user.email
 					orcidId: null # until v2 gets ORCID
+					v1UserId: user.overleaf?.id
 				destination:
 					brandVariationId: brand_variation_id
 				options:

services/web/test/unit/coffee/Exports/ExportsHandlerTests.coffee

@@ -72,6 +72,8 @@ describe 'ExportsHandler', ->
 				first_name: 'Arthur'
 				last_name: 'Author'
 				email: 'arthur.author@arthurauthoring.org'
+				overleaf:
+					id: 876
 			@rootDocPath = 'main.tex'
 			@historyVersion = 777
 			@ProjectGetter.getProject = sinon.stub().yields(null, @project)
@@ -104,6 +106,7 @@ describe 'ExportsHandler', ->
 						lastName: @user.last_name
 						email: @user.email
 						orcidId: null
+						v1UserId: 876
 					destination:
 						brandVariationId: @brand_variation_id
 					options:
@@ -135,6 +138,7 @@ describe 'ExportsHandler', ->
 						lastName: @custom_last_name
 						email: @user.email
 						orcidId: null
+						v1UserId: 876
 					destination:
 						brandVariationId: @brand_variation_id
 					options: