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/testdata/test.aconfig b/tools/aconfig/testdata/test.aconfig
index 015f295..d09396a 100644
--- a/tools/aconfig/testdata/test.aconfig
+++ b/tools/aconfig/testdata/test.aconfig
@@ -5,6 +5,7 @@
 # - first.values: DISABLED + READ_ONLY
 flag {
     name: "disabled_ro"
+    namespace: "aconfig_test"
     description: "This flag is DISABLED + READ_ONLY"
 }
 
@@ -12,6 +13,7 @@
 # - test.aconfig: DISABLED + READ_WRITE (default)
 flag {
     name: "disabled_rw"
+    namespace: "aconfig_test"
     description: "This flag is DISABLED + READ_WRITE"
 }
 
@@ -21,6 +23,7 @@
 # - second.values: ENABLED + READ_ONLY
 flag {
     name: "enabled_ro"
+    namespace: "aconfig_test"
     description: "This flag is ENABLED + READ_ONLY"
 }
 
@@ -29,5 +32,6 @@
 # - first.values: ENABLED + READ_WRITE
 flag {
     name: "enabled_rw"
+    namespace: "aconfig_test"
     description: "This flag is ENABLED + READ_WRITE"
 }