Auto merge of #20122 - o0Ignition0o:mach_run_nightly_windows, r=jdm

Windows support for the --nightly | -n flag to mach run commands.

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Add windows support to the -n flag.
---
Followup to #19947 , this PR will add windows support to the -n flag.
 This is part of step two for #19505

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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [ ] These changes fix #__ (github issue number if applicable).

The feature does not work just yet, I'm able to download and extract the archive, but it's not running the executable yet.
@tigercosmos might be a good reviewer on this one :)

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- [ ] There are tests for these changes OR
- [X] These changes do not require tests because they're part of a ./mach command.

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python/servo/command_base.py

@@ -402,8 +402,7 @@ class CommandBase(object):
         # Will alow us to fetch the relevant builds from the nightly repository
         os_prefix = "linux"
         if is_windows():
-            print("The nightly flag is not supported on windows yet.")
-            sys.exit(1)
+            os_prefix = "windows-msvc"
         if is_macosx():
             print("The nightly flag is not supported on mac yet.")
             sys.exit(1)
@@ -428,10 +427,13 @@ class CommandBase(object):
             sys.exit(1)
 
         nightly_target_directory = path.join(self.context.topdir, "target")
+        # ':' is not an authorized character for a file name on Windows
+        # make sure the OS specific separator is used
+        target_file_path = file_to_download.replace(':', '-').split('/')
+        destination_file = os.path.join(
+            nightly_target_directory, os.path.join(*target_file_path))
         # Once extracted, the nightly folder name is the tar name without the extension
         # (eg /foo/bar/baz.tar.gz extracts to /foo/bar/baz)
-        destination_file = path.join(
-            nightly_target_directory, file_to_download)
         destination_folder = os.path.splitext(destination_file)[0]
         nightlies_folder = path.join(
             nightly_target_directory, 'nightly', os_prefix)
@@ -457,11 +459,20 @@ class CommandBase(object):
             print("The nightly file {} has already been extracted.".format(
                 destination_folder))
         else:
-            print("Extracting to {}...".format(destination_folder))
-            with tarfile.open(os.path.join(nightlies_folder, destination_file), "r") as tar:
-                tar.extractall(destination_folder)
-
-        return path.join(destination_folder, "servo", "servo")
+            print("Extracting to {} ...".format(destination_folder))
+            if is_windows():
+                command = 'msiexec /a {} /qn TARGETDIR={}'.format(
+                    os.path.join(nightlies_folder, destination_file), destination_folder)
+                if subprocess.call(command, stdout=PIPE, stderr=PIPE) != 0:
+                    print("Could not extract the nightly executable from the msi package.")
+                    sys.exit(1)
+            else:
+                with tarfile.open(os.path.join(nightlies_folder, destination_file), "r") as tar:
+                    tar.extractall(destination_folder)
+        bin_folder = path.join(destination_folder, "servo")
+        if is_windows():
+            bin_folder = path.join(destination_folder, "PFiles", "Mozilla research", "Servo Tech Demo")
+        return path.join(bin_folder, "servo{}".format(BIN_SUFFIX))
 
     def build_env(self, hosts_file_path=None, target=None, is_build=False, geckolib=False, test_unit=False):
         """Return an extended environment dictionary."""