** Shares of Twenty-First Century Fox and UK's Sky dip after Comcast says abandons bid for Fox assets ** Shares of Rupert Murdoch's Fox fall 1.5 pct to $46.00 in premarket, Sky shares down 1.2 pct to a session low of 15.19 pounds; Comcast shares up 3 pct ** Disney rises 0.8 pct after Comcast drops Fox bid and says it will focus on its recommended offer for Sky ** Sky shares fall initially on the news but quickly pare those losses to trade marginally lower on LSE (Reporting by Muvija M in Bengaluru)