It took nearly two years, some 41 PGA Tour starts and a disappointing meltdown loss two weeks earlier in Phoenix, but Bubba Watson finally broke through for his first victory since the 2012 Masters, riding some spectacular weekend golf to victory at the Northern Trust Open in Los Angeles.  Watson reached the 36-hole mark well back in the pack following opening rounds of 70-71 - somewhat mediocre stuff in a week marked by perfect weather and firm, fast fairways.  But his was a very different game thereafter, as Watson became the first man in three decades to play the entire weekend at Riviera without a bogey, his flawless back-to-back rounds of 64 vaulting him over the field and, ultimately, to a two-shot victory.  Even after his Saturday effort, Watson began Sunday's final round five behind 54-hole leader William McGirt, but that ground was quickly covered via five birdies in his first eight holes en route to an outgoing 30.  One more birdie at the par-5 11th moved Watson to 14 under par, a number which none of his long list of pursuers was ever able to reach.  A closing birdie at the famed 475-yard 18th would ultimately clinch a two-shot triumph over Dustin Johnson, who shot a closing 66 and finished second for the second straight week..................Thirty-year-old South African Thomas Aiken claimed his 10th career victory and his third on the European Tour, coming from behind with a closing 67, then defeating England's Oliver Fisher on the first hole of sudden death in the Africa Open at the short but venerable East London Golf Club.  Behind opening rounds of 66-65-66, Aiken began Sunday four shots behind Argentina's young Emiliano Grillo, who'd launched himself to the top of the leaderboard with middle rounds of 63-62 over one of the E Tour's easiest scoring courses.  Having recently finished second in Dubai, Grillo seemed poised for a breakthrough victory, but those hopes were quickly dashed on Sunday when he stunningly took a nine on the 446-yard 1st hole before limping to the turn in an inglorious 43 strokes.  To his great credit, Grillo would ultimately rally to birdie the last five holes en route to tying for fifth, but by this time Aiken had notched key birdies at the 15th and 16th to draw even with the 25-year-old Fisher, who'd carded a second round 63 but on Sunday could manage no better than a 69, which left both players tied on 264.  Contested over the downhill 410-yard 18th, the playoff was a brief one as Aiken quickly rolled in a 30-footer for birdie to secure the title.  His victory continued a long trend of South African dominance of European Tour events played on home soil, as Aiken was the 10th home-grown winner in the last 13 such tournaments, the 36th overall in 58 all-time E Tour events, and the fifth straight in the five-year history of the African Open.