Auto merge of #13486 - UK992:mach-bootstrap-2, r=larsbergstrom

Fix msvc packages download dir for custom `.servo` location

- [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).

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python/servo/bootstrap_commands.py

@@ -145,7 +145,7 @@ class MachCommands(CommandBase):
     def bootstrap(self, android=False, interactive=False, force=False):
         from servo.bootstrapper.bootstrap import Bootstrapper
 
-        bootstrapper = Bootstrapper()
+        bootstrapper = Bootstrapper(self.context)
         bootstrapper.bootstrap(android=android, interactive=interactive, force=force)
 
     @Command('bootstrap-rust',

python/servo/bootstrapper/bootstrap.py

@@ -13,7 +13,7 @@ from windows_msvc import WindowsMsvcBootstrapper
 class Bootstrapper(object):
     """Main class that performs system bootstrap."""
 
-    def __init__(self):
+    def __init__(self, context):
         self.instance = None
         cls = None
         args = {}
@@ -28,6 +28,7 @@ class Bootstrapper(object):
             sys.exit('Bootstrap support is not yet available for your OS.')
 
         self.instance = cls(**args)
+        self.instance.context = context
 
     def bootstrap(self, android=False, interactive=False, force=False):
         self.instance.interactive = interactive

python/servo/bootstrapper/windows_msvc.py

@@ -23,7 +23,7 @@ class WindowsMsvcBootstrapper(BaseBootstrapper):
     def install_system_packages(self, packages=deps):
         from servo.bootstrap_commands import extract, download_file
 
-        deps_dir = os.path.join(".servo", "msvc-dependencies")
+        deps_dir = os.path.join(self.context.sharedir, "msvc-dependencies")
         deps_url = "https://servo-rust.s3.amazonaws.com/msvc-deps/"
         first_run = True