sorry, forgot to mention that this was a "Large Biome" world. I thought that would show up on the F3 screen...
Check to make sure you are not playing on peaceful
New picture with seed provided in pic added
Have you tried creating a new world to determine weather it is your save that has become corrupted or the game that has corrupted?
A block being powered by a repeater where the redstone block is in this post has the same effect
Re-created the world using the "re-create world" button. the bug did not happen again. No idea how to replicate what happened. My world now looks like the screenshot you sent...