StringUtil: Add PathToFileName function

Source/Core/Common/StringUtil.cpp

@@ -322,6 +322,13 @@ bool SplitPath(std::string_view full_path, std::string* path, std::string* filen
   return true;
 }
 
+std::string PathToFileName(std::string_view path)
+{
+  std::string file_name, extension;
+  SplitPath(path, nullptr, &file_name, &extension);
+  return file_name + extension;
+}
+
 void BuildCompleteFilename(std::string& complete_filename, std::string_view path,
                            std::string_view filename)
 {

Source/Core/Common/StringUtil.h

@@ -159,6 +159,8 @@ std::string JoinStrings(const std::vector<std::string>& strings, const std::stri
 bool SplitPath(std::string_view full_path, std::string* path, std::string* filename,
                std::string* extension);
 
+std::string PathToFileName(std::string_view path);
+
 void BuildCompleteFilename(std::string& complete_filename, std::string_view path,
                            std::string_view filename);
 

Source/Core/DolphinQt/Settings/InterfacePane.cpp

@@ -119,12 +119,9 @@ void InterfacePane::CreateUI()
   // List avalable themes
   auto theme_search_results =
       Common::DoFileSearch({File::GetUserPath(D_THEMES_IDX), File::GetSysDirectory() + THEMES_DIR});
-  for (const std::string& filename : theme_search_results)
+  for (const std::string& path : theme_search_results)
   {
-    std::string name, ext;
-    SplitPath(filename, nullptr, &name, &ext);
-    name += ext;
-    QString qt_name = QString::fromStdString(name);
+    const QString qt_name = QString::fromStdString(PathToFileName(path));
     m_combobox_theme->addItem(qt_name);
   }
 
@@ -137,12 +134,12 @@ void InterfacePane::CreateUI()
 
   m_combobox_userstyle->addItem(tr("(None)"), QString{});
 
-  for (const std::string& filename : userstyle_search_results)
+  for (const std::string& path : userstyle_search_results)
   {
-    std::string name, ext;
-    SplitPath(filename, nullptr, &name, &ext);
-    QString qt_name = QString::fromStdString(name);
-    m_combobox_userstyle->addItem(qt_name, QString::fromStdString(filename));
+    std::string name;
+    SplitPath(path, nullptr, &name, nullptr);
+    const QString qt_name = QString::fromStdString(name);
+    m_combobox_userstyle->addItem(qt_name, QString::fromStdString(path));
   }
 
   // Checkboxes

Source/Core/UICommon/GameFile.cpp

@@ -97,11 +97,9 @@ GameFile::GameFile() = default;
 
 GameFile::GameFile(std::string path) : m_file_path(std::move(path))
 {
-  {
-    std::string name, extension;
-    SplitPath(m_file_path, nullptr, &name, &extension);
-    m_file_name = name + extension;
+  m_file_name = PathToFileName(m_file_path);
 
+  {
     std::unique_ptr<DiscIO::Volume> volume(DiscIO::CreateVolume(m_file_path));
     if (volume != nullptr)
     {