WIP Chromite supporting "LEGACY" mode, as requested by Anush.

chromite/specs/chroot/_defaults

Index: chromite/specs/chroot/_defaults
diff --git a/chromite/specs/chroot/_defaults b/chromite/specs/chroot/_defaults
new file mode 100644
index 0000000000000000000000000000000000000000..9a68fd22e174194b3da8d6a4d59c40b6f1f932e1
--- /dev/null
+++ b/chromite/specs/chroot/_defaults
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+# This spec is used to prime the ConfigParser before reading any chroot specs.
+#
+# It can be thought of as the "superclass" of all chroot specs.
+#
+# It can refer to $(name)s to get the name of the chroot spec without the
+# ".spec" suffix (AKA the subclass's name).
+#
+# Use RFC 822 format
+
+
+[CHROOT]
+
+# The path to the chroot.  If relative, this is relative to the base of your
+# chromium source tree.  This is passed to make_chroot and enter_chroot as the
+# --chroot option.
+#
+# DEFAULT: the name of the subclass spec file, without the suffix
+path: %(name)s
+
+# Flags to pass to make_chroot (other than --chroot).
+#
+# DEFAULT: nothing
+make_chroot_flags:
+
+# Flags to pass to enter_chroot (other than --chroot).
+#
+# DEFAULT: nothing
+enter_chroot_flags: