buffet: Add support for 'default' properties in CDD
The internals of supporting optional command parameters/state
properties was built into buffet earlier, but this was not exposed
in JSON reading/writing routines, so it was impossible to use this
feature.
Added JSON serialization/deserialization code and unit tests
to verify the operation.
BUG=brillo:357
TEST=`FEATURES=test emerge-link buffet`
Change-Id: I29c8d3d7c0894a9c837e73d0fdb16bafdfadfeca
Reviewed-on: https://chromium-review.googlesource.com/253070
Trybot-Ready: Alex Vakulenko <avakulenko@chromium.org>
Tested-by: Alex Vakulenko <avakulenko@chromium.org>
Reviewed-by: Christopher Wiley <wiley@chromium.org>
Commit-Queue: Alex Vakulenko <avakulenko@chromium.org>
diff --git a/buffet/commands/schema_constants.h b/buffet/commands/schema_constants.h
index 6b06e2f..1cfbc75 100644
--- a/buffet/commands/schema_constants.h
+++ b/buffet/commands/schema_constants.h
@@ -34,6 +34,7 @@
// Command description JSON schema attributes.
extern const char kType[];
extern const char kDisplayName[];
+extern const char kDefault[];
extern const char kNumeric_Min[];
extern const char kNumeric_Max[];