aconfig: add namespace field to flag_declaration and parsed_flag

Add a new field to the proto messages flag_declaration and parsed_flag.

The new field will be used verbatim as a parameter when calling
DeviceConfig.getBoolean to read the value of a READ_WRITE flag. See the
DeviceConfig API for more info.

Note: not to be confused with the old namespace field, which has been
renamed to package.

Bug: 285211724
Test: atest aconfig.test
Change-Id: I2181be7b5e98fc334e5277fb5f7e386f1fe0b550
diff --git a/tools/aconfig/templates/cpp.template b/tools/aconfig/templates/cpp.template
index 331baaf..93f9b80 100644
--- a/tools/aconfig/templates/cpp.template
+++ b/tools/aconfig/templates/cpp.template
@@ -11,8 +11,8 @@
             virtual const bool value() \{
                 {{ if item.readwrite- }}
                 return GetServerConfigurableFlag(
-                    "{package}",
-                    "{item.flag_name}",
+                    "{item.device_config_namespace}",
+                    "{item.device_config_flag}",
                     "{item.default_value}") == "true";
                 {{ -else- }}
                 return {item.default_value};