OOC: I don't think the war would have lasted until December '45, even if the Japanese had won Midway bigtime.
Why? Because the atomic bomb was coming in August 1945 regardless. All the US needed was a base within bombing range, i.e., the Marianas.
OTL the Marianas fell in the summer of 1944. I could see a loss of Midway delaying this by three months, no problem. Six months, maybe. But by the spring of 1945, either Saipan or Tinian would be in US hands.
Also, while Yalta would probably play out differently, the US would still lobby Stalin to join the war, and he'd still agree. Why not? So in August 1945 the USSR still invades Manchuria and Korea.
So, the war still ends around the same time as OTL.
Which is not to say this isn't interesting! Differences in the course of the war could have huge knock-on effects down the line.
Doug M.