SdkService: Add delete endpoint.

BUG=b:142800964
TEST=run_tests

Change-Id: I7952d895066ee0044d3474a1c832ad98fb2d881f
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/chromite/+/1865689
Commit-Queue: Alex Klein <saklein@chromium.org>
Tested-by: Alex Klein <saklein@chromium.org>
Auto-Submit: Alex Klein <saklein@chromium.org>
Reviewed-by: Michael Mortensen <mmortensen@google.com>
diff --git a/api/controller/sdk.py b/api/controller/sdk.py
index 54eb043..e48dc23 100644
--- a/api/controller/sdk.py
+++ b/api/controller/sdk.py
@@ -82,3 +82,10 @@
     # This should be very rare, if ever used, but worth noting.
     cros_build_lib.Die('No chroot version could be found. There was likely an'
                        'error creating the chroot that was not detected.')
+
+
+@faux.all_empty
+@validate.validation_complete
+def Delete(input_proto, _output_proto, _config):
+  """Delete a chroot."""
+  sdk.Delete(chroot_path=input_proto.chroot.path)