Output properties before sets in snapshot module

This ensures a consistent output irrespective of whether property sets
are created before or after the properties are added. This provides a
little more flexibility in the creation code which allows that to be
simplfied.

Also switches from using reflection to a type switch.

Bug: 142918168
Test: m nothing
Change-Id: Ia025bfc751f1217d1658de6fb8e15091ea0ea9ff

sdk/cc_sdk_test.go

@@ -1212,12 +1212,12 @@ module_exports_snapshot {
     name: "myexports@current",
     device_supported: false,
     host_supported: true,
+    native_static_libs: ["myexports_mynativelib@current"],
     target: {
         host: {
             compile_multilib: "64",
         },
     },
-    native_static_libs: ["myexports_mynativelib@current"],
 }`),
 		checkAllCopyRules(`
 include/Test.h -> include/include/Test.h