Interesting bit of trivia, and each site you look at on line will give you a different answer. The MAJESTIC class light carrier came with bofors, but the Bonnie did not. Some sources will state that, yes, they were there, and some will confrim just what Sledge said. The actual answer is in between, and it satisfies all theories and urban legends. Armament: 4x twin mountings, 3"-50cal. anti-aircraft guns (two removed after refit in 67). 8x 40 mm Bofors anti-aircraft guns. ( aapparently never installed )
From the DND site, : "When PROTECTEUR was first constructed she had a twin 3 inch (76mm) gun mounted on her bow. In 1983, they were removed as the guns were deemed as no longer being effective. When Iraq invaded Kuwait on 2 August 1990, the Canadian Government decided to sent three ships; one of which was PROTECTEUR. Before being deployed twenty days later on 24 August 1990, PROTECTEUR was rearmed with the twin 3 inch gun, two CIWS (Close In Weapon Systems, a gun designed to destroy incoming missiles) and two Bofors 20mm guns. The Bofors guns were originally from the BONAVENTURE. After BONAVENTURE's decommissioning the guns were loaned to a Halifax museum and then borrowed back in 1990 for the Gulf War.
This leads me to believe that Bonnie came with 40mm, and they were left uncrated and/or used elsewhere.