A shiny Generation V starter might be coming to Pokemon GO very soon. ... If Dewott is evolved into Samurott during the Community Day (or up till two hours later), ...

Oshawott evolves into Dewott, and Dewott evolves into Samurott which, during the event, will have the exclusive move Hydro Cannon! ... And yes, Oshawott will potentially be a SHINY Oshawott.