CRA states that T1135s are prepared without regard to the attribution rules

CRA considers that the attribution rules should be ignored for T1135 purposes so that, for example, an individual who received a spousal gift of the cash used to purchase her share of a specified foreign property would compute whether she was over the $100,000 cost amount threshold and report her share of the income on the form without regard to the application of the attribution rules.

Neal Armstrong. Summary of 24 February 2017 External T.I. 2016-0669081E5 under s. 233.3(1) – reporting entity.