Mirrors the change from 8e82c6ab1b%5E%21/
Also adds a new variable needed to build ToT ANGLE. This is because the toolchain change is unfortunately linked to rolling ANGLE at the same time, since the current ANGLE pull has build errors under VS 2017, but ToT hits internal compiler errors with the old toolchain, so they need to be updated in lockstep.
Part of fix for https://github.com/flutter/flutter/issues/48831
This adds minimal (in some cases dummy) files sufficient to allow
building ANGLE in this buildroot using the build_with_chromium
option.
This relanded version uses the new swiftshader_ prefixed versions of the
DLL names in the swiftshader build, which are loaded preferentially if
available. This ensures that the swiftshader tests will use those,
rather than the potentially incompatible ANGLE versions. In local
testing, this resolved the ShellTest failures that led to the previous
revert.
Reland of fe3b82877e (#276)
This adds minimal (in some cases dummy) files sufficient to allow
building ANGLE in this buildroot using the build_with_chromium option.
