Google hasn't withdrawn all patent claims against Microsoft, though
From DailyTech:
On Microsoft's side, it was looking to license two standards-essential patents for H.264, which Google controls. However, Microsoft didn't want to license these patents on royalty terms with Google.Google Ditches Patent Claim Against Microsoft for Xbox Video Compression
It appears that Google has dropped the patent claim, though. But Google hasn't withdrawn all patent claims against Microsoft. In Washington state and Germany, Google is still going after Microsoft for SEP injunctions in pending lawsuits.
