rust: Add features list to rust_project.json

Bug: 183679729
Test: SOONG_GEN_RUST_PROJECT=1 m nothing
Test: manually check v1 feature resolution for libprofcollectd
Change-Id: Ib59b63372865f7f4545fe327e92d1642d76ce9c9
diff --git a/rust/project_json.go b/rust/project_json.go
index 8d3d250..c28bc7b 100644
--- a/rust/project_json.go
+++ b/rust/project_json.go
@@ -49,7 +49,7 @@
 	RootModule  string            `json:"root_module"`
 	Edition     string            `json:"edition,omitempty"`
 	Deps        []rustProjectDep  `json:"deps"`
-	Cfgs        []string          `json:"cfgs"`
+	Cfg         []string          `json:"cfg"`
 	Env         map[string]string `json:"env"`
 }
 
@@ -230,7 +230,7 @@
 		RootModule:  rootModule,
 		Edition:     comp.edition(),
 		Deps:        make([]rustProjectDep, 0),
-		Cfgs:        make([]string, 0),
+		Cfg:         make([]string, 0),
 		Env:         make(map[string]string),
 	}
 
@@ -238,6 +238,10 @@
 		crate.Env["OUT_DIR"] = comp.CargoOutDir().String()
 	}
 
+	for _, feature := range comp.Properties.Features {
+		crate.Cfg = append(crate.Cfg, "feature=\""+feature+"\"")
+	}
+
 	deps := make(map[string]int)
 	singleton.mergeDependencies(ctx, rModule, &crate, deps)