[permission_handler] Refactor the C++ code

[swift-kim]

Part of the code refactoring project.

app_settings_manager.cc:

• Remove the AppPermissions class and move its logic to AppSettingsManager::OpenAppSettings. The class has been first introduced in [permission_handler] Revise OpenAppSettings #142, but adds unnecessary complexity to the code.
• Replace the PackageName class with a simple function GetPackageName.

permission_handler_tizen_plugin.cc & permission_manager.cc:

• The code has almost been rewritten from scratch (reduced 200~ lines of code).
• The PermissionManager class is a copy of image_picker_tizen's PermissionManager. (See [image_picker] Refactor the C++ code #353.)
  • The only difference is that PermissionStatus and PermissionResult are now a single type, in accordance with the type defined in the platform interface package.
• Rename PermissionGroup to Permission.
• Remove all on_success and on_error callbacks as everything is now done synchronously.
• Iterating over requested permissions is done inside HandleMethodCall's if-else block.
• Do not redundantly check for the permission status before requesting it.
• Remove duplication of kLocation results as it's not expected by anybody.

service_manager.cc:

• Make ServiceManager::CheckServiceStatus synchronous.

[HakkyuKim]

Looks nice! LGTM.

[swift-kim]

Let me test this change on TV tomorrow. Now this plugin is expected to work on TV (although not necessary because all permissions are already granted) and we don't have to explicitly exclude the permission_handler dependency from other plugins tests.

[swift-kim]

Tested on a TV emulator and it worked.