[android] add FD_DEV_FEATURES in env loader (#3493)

This environment variable fixes some glitches in OneUI 7 and HyperOS 3.

Thanks StevenMX for letting me know.

Reviewed-on: https://git.eden-emu.dev/eden-emu/eden/pulls/3493
Reviewed-by: CamilleLaVey <camillelavey99@gmail.com>
Co-authored-by: MrPurple666 <antoniosacramento666usa@gmail.com>
Co-committed-by: MrPurple666 <antoniosacramento666usa@gmail.com>

src/android/app/src/main/java/org/yuzu/yuzu_emu/fragments/FreedrenoSettingsFragment.kt

@@ -1,4 +1,4 @@
-// SPDX-FileCopyrightText: Copyright 2025 Eden Emulator Project
+// SPDX-FileCopyrightText: Copyright 2026 Eden Emulator Project
 // SPDX-License-Identifier: GPL-3.0-or-later
 
 package org.yuzu.yuzu_emu.fragments
@@ -110,7 +110,7 @@ class FreedrenoSettingsFragment : Fragment() {
         val commonVars = listOf(
             "TU_DEBUG", "FD_MESA_DEBUG", "IR3_SHADER_DEBUG",
             "FD_RD_DUMP", "FD_RD_DUMP_FRAMES", "FD_RD_DUMP_TESTNAME",
-            "TU_BREADCRUMBS"
+            "TU_BREADCRUMBS", "FD_DEV_FEATURES"
         )
 
         for (varName in commonVars) {

src/android/app/src/main/java/org/yuzu/yuzu_emu/utils/NativeFreedrenoConfig.kt

@@ -1,4 +1,4 @@
-// SPDX-FileCopyrightText: Copyright 2025 Eden Emulator Project
+// SPDX-FileCopyrightText: Copyright 2026 Eden Emulator Project
 // SPDX-License-Identifier: GPL-3.0-or-later
 
 package org.yuzu.yuzu_emu.utils
@@ -144,6 +144,15 @@ object FreedrenoPresets {
         )
     )
 
+    val DEV_FEATURES_UBWC_HINT = FreedrenoPreset(
+        name = "Dev - UBWC Flag Hint",
+        description = "Enable TP UBWC flag hint for development",
+        icon = "ic_dev_features",
+        variables = mapOf(
+            "FD_DEV_FEATURES" to "enable_tp_ubwc_flag_hint=1"
+        )
+    )
+
     val PERFORMANCE_DEFAULT = FreedrenoPreset(
         name = "Performance - Default",
         description = "Clear all debug options for performance",
@@ -159,6 +168,7 @@ object FreedrenoPresets {
         CAPTURE_FRAMES,
         SHADER_DEBUG,
         GPU_HANG_TRACE,
+        DEV_FEATURES_UBWC_HINT,
         PERFORMANCE_DEFAULT
     )
 }

src/android/app/src/main/jni/native_freedreno.cpp

@@ -1,4 +1,4 @@
-// SPDX-FileCopyrightText: Copyright 2025 Eden Emulator Project
+// SPDX-FileCopyrightText: Copyright 2026 Eden Emulator Project
 // SPDX-License-Identifier: GPL-3.0-or-later
 
 /**
@@ -258,6 +258,11 @@ Java_org_yuzu_yuzu_1emu_utils_NativeFreedrenoConfig_setFreedrenoEnv(
     }
 
     LOG_INFO(Frontend, "[Freedreno] Set {}={}", var_name, value);
+
+    if (var_name == "FD_DEV_FEATURES") {
+        LOG_INFO(Frontend, "[Freedreno] FD_DEV_FEATURES enabled: {}", value);
+    }
+
     return JNI_TRUE;
 }