CMake: Fix GTK3 Win32 build

Add 'BEFORE' to target_include_directories so we include the headers
of the buildin third-party libraries before headers of third-party
libraries included in wxTOOLKIT_INCLUDE_DIRS.

build/cmake/functions.cmake

@@ -378,7 +378,7 @@ macro(wx_lib_include_directories name)
         list(APPEND wxMONO_INCLUDE_DIRS_PUBLIC ${_LIB_INCLUDE_DIRS_PUBLIC})
         list(APPEND wxMONO_INCLUDE_DIRS_PRIVATE ${_LIB_INCLUDE_DIRS_PRIVATE})
     else()
-        target_include_directories(${name};${ARGN})
+        target_include_directories(${name};BEFORE;${ARGN})
     endif()
 endmacro()
 

build/cmake/lib/adv/CMakeLists.txt

@@ -18,7 +18,11 @@ if(WXMSW)
 elseif(WXOSX_COCOA)
     wx_append_sources(ADV_FILES ADVANCED_OSX_COCOA)
 elseif(WXGTK)
+    if(WXGTK2)
         wx_append_sources(ADV_FILES ADVANCED_GTK2)
+    else()
+        wx_append_sources(ADV_FILES ADVANCED_GTK)
+    endif()
     wx_append_sources(ADV_FILES ADVANCED_GTK_NATIVE)
 endif()
 

build/cmake/lib/aui/CMakeLists.txt

@@ -13,7 +13,7 @@ wx_append_sources(AUI_FILES AUI_CMN)
 
 if(WXMSW)
     wx_append_sources(AUI_FILES AUI_MSW)
-elseif(WXGTK)
+elseif(WXGTK2)
     wx_append_sources(AUI_FILES AUI_GTK)
 endif()
 

build/cmake/lib/core/CMakeLists.txt

@@ -25,8 +25,13 @@ if(WXMSW)
     wx_append_sources(CORE_SRC MSW)
     wx_append_sources(CORE_SRC MSW_DESKTOP)
 elseif(WXGTK)
+    if(WXGTK2)
         wx_append_sources(CORE_SRC GTK2_LOWLEVEL)
         wx_append_sources(CORE_SRC GTK2)
+    else()
+        wx_append_sources(CORE_SRC GTK_LOWLEVEL)
+        wx_append_sources(CORE_SRC GTK)
+    endif()
 
     wx_append_sources(CORE_SRC XWIN_LOWLEVEL)
 elseif(WXOSX_COCOA)