Change default value of setElegantTextFlag

As a first step of deprecating UI fonts, make setElegantTextFlag as true
by default if the target SDK is set to Android 15 or later..

Bug: 279646685
Test: atest PaintDefaultsTest
Change-Id: If8e40c075122cafd2f89ae703bf6a5f07ebc7bd0
diff --git a/libs/hwui/FeatureFlags.h b/libs/hwui/FeatureFlags.h
index ffb329d..00d049c 100644
--- a/libs/hwui/FeatureFlags.h
+++ b/libs/hwui/FeatureFlags.h
@@ -33,6 +33,14 @@
 #endif  // __ANDROID__
 }
 
+inline bool deprecate_ui_fonts() {
+#ifdef __ANDROID__
+    return com_android_text_flags_deprecate_ui_fonts();
+#else
+    return true;
+#endif  // __ANDROID__
+}
+
 }  // namespace text_feature
 
 }  // namespace android