CMake: move GTK+ check into wxWidgets

CMakeLists.txt

@@ -795,30 +795,6 @@ if(NOT DISABLE_WX)
     add_definitions(-DwxSIZE_T_IS_UINT)
   endif()
 
-  if(UNIX AND NOT APPLE AND NOT HAIKU)
-    # There is a bug in the FindGTK module in cmake version 2.8.2 that
-    # does not find gdk-pixbuf-2.0.  On the other hand some 2.8.3
-    # users have complained that pkg-config does not find
-    # gdk-pixbuf-2.0.  On yet another hand, cmake version 2.8.3 in
-    # Ubuntu Natty does not find the glib libraries correctly.
-    # Ugly!!!
-    execute_process(COMMAND lsb_release -c -s
-        OUTPUT_VARIABLE DIST_NAME
-        ERROR_QUIET OUTPUT_STRIP_TRAILING_WHITESPACE)
-    if(${CMAKE_MAJOR_VERSION}.${CMAKE_MINOR_VERSION}.${CMAKE_PATCH_VERSION}
-        VERSION_EQUAL 2.8.2 OR "${DIST_NAME}" STREQUAL "natty")
-      check_lib(GTK2 gtk+-2.0 gtk+-2.0 gtk.h REQUIRED)
-    else()
-      find_package(GTK2)
-      if(GTK2_FOUND)
-        include_directories(${GTK2_INCLUDE_DIRS})
-        list(APPEND LIBS ${GTK2_LIBRARIES})
-      else()
-        message(FATAL_ERROR "GTK is required to build the WX UI. Please install the GTK development libraries.")
-      endif()
-    endif()
-  endif()
-
   if(wxWidgets_FOUND)
     include(${wxWidgets_USE_FILE})
     message(STATUS "wxWidgets found, enabling GUI build")

Externals/wxWidgets3/CMakeLists.txt

@@ -860,6 +860,8 @@ elseif(${CMAKE_SYSTEM_NAME} MATCHES "Linux|FreeBSD")
 	if (NOT X11_xf86vmode_FOUND OR NOT X11_Xinerama_FOUND)
 		message(FATAL_ERROR "wxGTK2 needs Xinerama and Xxf86vm")
 	endif()
+        find_package(GTK2 REQUIRED)
+        target_include_directories(wx PUBLIC ${GTK2_INCLUDE_DIRS})
         target_link_libraries(wx PRIVATE
 		png
 		${GTHREAD2_LIBRARIES}