Several weeks before he massacred 49 at an Orlando gay nightclub, Muslim terrorist Omar Seddique Mateen transferred over his interest in his Florida home to his older sister and Afghan brother-in-law, property records show — an indication the family possibly had some knowledge of his martyrdom plans. Authorities say the fatally shot Mateen clearly was prepared to die in a gun battle with police during the June 12 attack, the deadliest act of terrorism on U.S. soil since 9/11. On April 5, Mateen “quit-claimed” the deed on his Port St. Lucie, Fla., house, signing it over to his sister, Sabrina...