Sounds good. I might poke at the task a bit to see if there are any easy wins, or I might leave it for the Angle team to do or ignore.
Angle's use of windows.h isn't bleeding over into Chromium so it doesn't affect me directly, it just shows up on the reports I generate of windows.h usage by directory so I thought I'd ask. The reports look something like this:
Found 6053 .obj files (15.9%) that used um/windows.h, 31954 that did not.
Windows.h usage by directory: