Show current display server in Editor window tooltip

(cherry picked from commit 62968dd437)

Source/Engine/Platform/Base/PlatformBase.cpp

@@ -262,6 +262,15 @@ PlatformType PlatformBase::GetPlatformType()
     return PLATFORM_TYPE;
 }
 
+#if !PLATFORM_SDL
+
+String PlatformBase::GetDisplayServer()
+{
+    return String::Empty;
+}
+
+#endif
+
 bool PlatformBase::Is64BitApp()
 {
 #if PLATFORM_64BITS

Source/Engine/Platform/Base/PlatformBase.h

@@ -369,6 +369,11 @@ public:
     /// </summary>
     API_PROPERTY() static PlatformType GetPlatformType();
 
+    /// <summary>
+    /// Returns the display server name on Linux.
+    /// </summary>
+    API_PROPERTY() static String GetDisplayServer() = delete;
+
     /// <summary>
     /// Returns true if is running 64 bit application (otherwise 32 bit). It's compile-time constant.
     /// </summary>