Call system_setting_get_* before calling system_setting_set_change_cb

Based on BT, two issues can be expected.
First, a problem could occur in vconf when calling the setting getter while the system is not fully initialized. Alternatively, a deadlock could occur on the same conf when calling the setting getter after registering the changed callback.

Since this issue did not occur after a reboot or subsequent routines, it is likely a timing issue due to the callback rather than an initialization issue. Therefore, the problem can be prevented by calling the setting getter before registering the changed callback.

```
crash dump

 (gdb) bt
 #0  0x0000ffff94a13524 in __GI___poll (fds=0xfffff49d3830, nfds=1,
     timeout=<optimized out>) at ../sysdeps/unix/sysv/linux/poll.c:41
 #1  0x0000ffff938f44e8 in ?? () from /lib64/libbuxton2.so.1
 flutter-tizen#2  0x0000ffff938f6ac0 in buxton_get_value_sync () from /lib64/libbuxton2.so.1
 flutter-tizen#3  0x0000ffff93703af8 in ?? () from /lib64/libvconf.so.0
 flutter-tizen#4  0x0000ffff937052c4 in vconf_get_int () from /lib64/libvconf.so.0
 flutter-tizen#5  0x0000ffff8c1b9604 in ?? () from /lib64/libcapi-system-system-settings.so.0
 flutter-tizen#6  0x0000ffff8c1b390c in system_settings_get_value_int ()
    from /lib64/libcapi-system-system-settings.so.0
 flutter-tizen#7  0x0000ffff8c2ec3d0 in ?? ()
    from /usr/apps/org.tizen.homescreen/bin/../lib/libflutter_tizen_common.so
 flutter-tizen#8  0x0000ffff8c2ec330 in ?? ()
    from /usr/apps/org.tizen.homescreen/bin/../lib/libflutter_tizen_common.so
 flutter-tizen#9  0x0000ffff8c2f538c in ?? ()
    from /usr/apps/org.tizen.homescreen/bin/../lib/libflutter_tizen_common.so
 flutter-tizen#10 0x0000ffff8c2f3d70 in FlutterDesktopViewCreateFromNewWindow ()
    from /usr/apps/org.tizen.homescreen/bin/../lib/libflutter_tizen_common.so
 flutter-tizen#11 0x0000ffff94fd8ff4 in ?? () from /usr/apps/org.tizen.homescreen/bin/runner
 flutter-tizen#12 0x0000ffff94fd8df0 in ?? () from /usr/apps/org.tizen.homescreen/bin/runner
 flutter-tizen#13 0x0000ffff918b3df8 in ?? () from /usr/lib64/libcapi-appfw-application.so.0
 flutter-tizen#14 0x0000ffff919efc6c in tizen_cpp::AppCoreBase::Init(int, char**) ()
    from /lib64/libapp-core-cpp.so.1
 flutter-tizen#15 0x0000ffff919efd24 in tizen_cpp::AppCoreBase::Run(int, char**) ()
    from /lib64/libapp-core-cpp.so.1
 flutter-tizen#16 0x0000ffff91a34bdc in tizen_cpp::AppCoreUiBase::DoRun(int, char**) ()
    from /lib64/libapp-core-ui-cpp.so.1
 flutter-tizen#17 0x0000ffff91a34f4c in tizen_cpp::AppCoreUiBase::Impl::Run(int, char**) ()
    from /lib64/libapp-core-ui-cpp.so.1
 flutter-tizen#18 0x0000ffff918b3fa8 in ui_app_main ()
    from /usr/lib64/libcapi-appfw-application.so.0
 flutter-tizen#19 0x0000ffff94fd93a0 in ?? () from /usr/apps/org.tizen.homescreen/bin/runner
 flutter-tizen#20 0x0000ffff94fd8a8c in main ()
    from /usr/apps/org.tizen.homescreen/bin/runner
 flutter-tizen#21 0x0000aaaae7065bac in launchpad::loader::LaunchpadLoader::OnTerminate(int, char**) ()
 flutter-tizen#22 0x0000ffff94e2a030 in launchpad_loader_main ()
    from /lib64/liblaunchpad.so.0
 flutter-tizen#23 0x0000aaaae7063b58 in launchpad::loader::LaunchpadLoader::Run() ()
 flutter-tizen#24 0x0000aaaae7063500 in main ()
```

Author: JSUYA

flutter/shell/platform/tizen/channels/settings_channel.cc

@@ -4,8 +4,6 @@
 
 #include "settings_channel.h"
 
-#include <system/system_settings.h>
-
 #include "flutter/shell/platform/common/json_message_codec.h"
 
 namespace flutter {
@@ -25,21 +23,26 @@ SettingsChannel::SettingsChannel(BinaryMessenger* messenger)
           messenger,
           kChannelName,
           &JsonMessageCodec::GetInstance())) {
+  SetUpLocaleTimeFormat();
+  SetUpTextScaleFactor();
+  SendSettingsEvent();
+
   system_settings_set_changed_cb(
       SYSTEM_SETTINGS_KEY_LOCALE_TIMEFORMAT_24HOUR,
       [](system_settings_key_e key, void* user_data) -> void {
         auto* self = static_cast<SettingsChannel*>(user_data);
+        self->SetUpLocaleTimeFormat();
         self->SendSettingsEvent();
       },
       this);
   system_settings_set_changed_cb(
       SYSTEM_SETTINGS_KEY_FONT_SIZE,
       [](system_settings_key_e key, void* user_data) -> void {
         auto* self = static_cast<SettingsChannel*>(user_data);
+        self->SetUpTextScaleFactor();
         self->SendSettingsEvent();
       },
       this);
-  SendSettingsEvent();
 }
 
 SettingsChannel::~SettingsChannel() {
@@ -51,23 +54,24 @@ SettingsChannel::~SettingsChannel() {
 void SettingsChannel::SendSettingsEvent() {
   rapidjson::Document event(rapidjson::kObjectType);
   rapidjson::MemoryPoolAllocator<>& allocator = event.GetAllocator();
-  event.AddMember(kTextScaleFactorKey, GetTextScaleFactor(), allocator);
-  event.AddMember(kAlwaysUse24HourFormatKey, Prefer24HourTime(), allocator);
+
+  event.AddMember(kTextScaleFactorKey, text_scale_factor_, allocator);
+  event.AddMember(kAlwaysUse24HourFormatKey, locale_time_format_, allocator);
   event.AddMember(kPlatformBrightnessKey, "light", allocator);
   channel_->Send(event);
 }
 
-bool SettingsChannel::Prefer24HourTime() {
+bool SettingsChannel::SetUpLocaleTimeFormat() {
   bool value = false;
   if (system_settings_get_value_bool(
           SYSTEM_SETTINGS_KEY_LOCALE_TIMEFORMAT_24HOUR, &value) ==
       SYSTEM_SETTINGS_ERROR_NONE) {
-    return value;
+    locale_time_format_ = value;
   }
-  return false;
+  return locale_time_format_;
 }
 
-float SettingsChannel::GetTextScaleFactor() {
+float SettingsChannel::SetUpTextScaleFactor() {
   const float small = 0.8;
   const float normal = 1.0;
   const float large = 1.5;
@@ -79,18 +83,23 @@ float SettingsChannel::GetTextScaleFactor() {
       SYSTEM_SETTINGS_ERROR_NONE) {
     switch (value) {
       case SYSTEM_SETTINGS_FONT_SIZE_SMALL:
-        return small;
+        text_scale_factor_ = small;
+        break;
       case SYSTEM_SETTINGS_FONT_SIZE_LARGE:
-        return large;
+        text_scale_factor_ = large;
+        break;
       case SYSTEM_SETTINGS_FONT_SIZE_HUGE:
-        return huge;
+        text_scale_factor_ = huge;
+        break;
       case SYSTEM_SETTINGS_FONT_SIZE_GIANT:
-        return giant;
+        text_scale_factor_ = giant;
+        break;
       default:
-        return normal;
+        text_scale_factor_ = normal;
+        break;
     }
   }
-  return normal;
+  return text_scale_factor_;
 }
 
 }  // namespace flutter

flutter/shell/platform/tizen/channels/settings_channel.h

@@ -5,6 +5,7 @@
 #ifndef EMBEDDER_SETTINGS_CHANNEL_H_
 #define EMBEDDER_SETTINGS_CHANNEL_H_
 
+#include <system/system_settings.h>
 #include <memory>
 
 #include "flutter/shell/platform/common/client_wrapper/include/flutter/basic_message_channel.h"
@@ -20,10 +21,12 @@ class SettingsChannel {
 
  private:
   void SendSettingsEvent();
-  bool Prefer24HourTime();
-  float GetTextScaleFactor();
+  bool SetUpLocaleTimeFormat();
+  float SetUpTextScaleFactor();
 
   std::unique_ptr<BasicMessageChannel<rapidjson::Document>> channel_;
+  bool locale_time_format_ = false;
+  float text_scale_factor_ = SYSTEM_SETTINGS_FONT_SIZE_NORMAL;
 };
 
 }  // namespace flutter