Add support for Windows host

[ahumesky]

android_ndk_repository in rules.bzl is currently hard-coded for Linux.

[oakad]

I've got one of my projects compiling fine with rules_android_ndk on Linux and now want to do so on Windows. Alas, as of right now it's still "Unsupported operating system: windows 10".

If something happens in the Windows support direction, I will be happy to test whatever changes are there. :-)

[oakad]

Windows is still the most used platform by Android devs (AFAIK). By having NDK broken on Bazel/Windows (as people keep upgrading their NDKs), you're essentially telling us to drop Bazel and go look elsewhere.

The ongoing campaign of closing all the old Bazel issues without ever fixing most of them is also not encouraging trust. :-)

[master-hax]

+1 interested in Windows support

[marcushultman]

I must be missing something, but it seems like I can't even use this repository_rule since I need to be able to configure my WORKSPACE on multiple platforms (including windows). Even if no target depend on the repository, the whole setup errors out when configuring. How can optionally call android_ndk_repository based on platform from my WORKSPACE?

[ahumesky]

In preparation for this, an updated NDK needs to be added with the Windows BazeCI image: bazelbuild/continuous-integration#1962

[ahumesky]

@marcushultman see https://stackoverflow.com/questions/78122191/bazel-its-possible-to-download-different-external-dependencies-depending-on-the for some advice on making this work across different platforms

[oakad]

These news are most welcome. :-)