[SB] Update font for status bar clock & carrier text.

(Carrier text also uses the TextAppearance.StatusBar.Clock style.)

Bug: 393609116
Flag: com.android.systemui.status_bar_font_updates
Test: Enable flag -> see new font
Change-Id: I4f50f9e4b952a55f55d0f793ee00414402307841
diff --git a/packages/SystemUI/Android.bp b/packages/SystemUI/Android.bp
index 5b48566..a4dc709 100644
--- a/packages/SystemUI/Android.bp
+++ b/packages/SystemUI/Android.bp
@@ -429,6 +429,7 @@
     manifest: "AndroidManifest-res.xml",
     flags_packages: [
         "android.app.flags-aconfig",
+        "com_android_systemui_flags",
     ],
 }
 
diff --git a/packages/SystemUI/aconfig/systemui.aconfig b/packages/SystemUI/aconfig/systemui.aconfig
index ab18612..54632d6 100644
--- a/packages/SystemUI/aconfig/systemui.aconfig
+++ b/packages/SystemUI/aconfig/systemui.aconfig
@@ -544,6 +544,14 @@
 }
 
 flag {
+  name: "status_bar_font_updates"
+  namespace: "systemui"
+  description: "Read only flag for using a new font in the status bar"
+  bug: "393609116"
+  is_fixed_read_only: true
+}
+
+flag {
     name: "promote_notifications_automatically"
     namespace: "systemui"
     description: "Flag to automatically turn certain notifications into promoted notifications so "
diff --git a/packages/SystemUI/res/values/styles.xml b/packages/SystemUI/res/values/styles.xml
index 7895ff7..a479f18 100644
--- a/packages/SystemUI/res/values/styles.xml
+++ b/packages/SystemUI/res/values/styles.xml
@@ -19,7 +19,8 @@
 
     <style name="TextAppearance.StatusBar.Clock" parent="@*android:style/TextAppearance.StatusBar.Icon">
         <item name="android:textSize">@dimen/status_bar_clock_size</item>
-        <item name="android:fontFamily">@*android:string/config_headlineFontFamilyMedium</item>
+        <item name="android:fontFamily" android:featureFlag="!com.android.systemui.status_bar_font_updates">@*android:string/config_headlineFontFamilyMedium</item>
+        <item name="android:fontFamily" android:featureFlag="com.android.systemui.status_bar_font_updates">"variable-label-large-emphasized"</item>
         <item name="android:textColor">@color/status_bar_clock_color</item>
         <item name="android:fontFeatureSettings">tnum</item>
     </style>