Add aconfig flags for rust keystore2

Test: m keystore2
Change-Id: I0bdd3d34a4e78500b266b8aac321ff1e2903dffb
diff --git a/keystore2/Android.bp b/keystore2/Android.bp
index b8db7c6..4792e8a 100644
--- a/keystore2/Android.bp
+++ b/keystore2/Android.bp
@@ -28,6 +28,7 @@
     defaults: [
         "keymint_use_latest_hal_aidl_rust",
         "keystore2_use_latest_aidl_rust",
+        "framework-minus-apex-aconfig-libraries",
     ],
 
     rustlibs: [
@@ -42,6 +43,7 @@
         "android.security.metrics-rust",
         "android.security.rkp_aidl-rust",
         "libanyhow",
+        "libkeystore2_flags_rust",
         "libbinder_rs",
         "libkeystore2_aaid-rust",
         "libkeystore2_apc_compat-rust",
@@ -146,3 +148,16 @@
     ],
     afdo: true,
 }
+
+// Keystore Flag definitions
+aconfig_declarations {
+    name: "keystore2_flags",
+    package: "android.security.keystore2",
+    srcs: ["aconfig/flags.aconfig"],
+}
+
+rust_aconfig_library {
+    name: "libkeystore2_flags_rust",
+    crate_name: "keystore2_flags",
+    aconfig_declarations: "keystore2_flags",
+}
diff --git a/keystore2/aconfig/flags.aconfig b/keystore2/aconfig/flags.aconfig
new file mode 100644
index 0000000..04bbddc
--- /dev/null
+++ b/keystore2/aconfig/flags.aconfig
@@ -0,0 +1,8 @@
+package: "android.security.keystore2"
+
+flag {
+  name: "wal_db_journalmode"
+  namespace: "hardware_backed_security"
+  description: "This flag controls changing journalmode to wal"
+  bug: "191777960"
+}