fix Visual Studio toolchain detection (#628)
fix Visual Studio toolchain detection (#628)

Some VS packages may install redistributables in same folder than
toolchains, under the name "v143" for instance (starting with a 'v').

In this case, an exception is thrown, as function
_SortByHighestVersionNumberFirst does not expect this.

The fix was taken from dart-sdk, that itself takes it from Chromium:
https://chromium-review.googlesource.com/c/chromium/src/+/2645652
flutter/buildroot,flutter/buildroot,flutter/buildroot,flutter/buildroot