Only link webview library with libwebkitgtk in wxGTK, not the core one.

Add EXTRALIBS_WEBVIEW similar to the existing EXTRALIBS_MEDIA and such and set
it in configure instead of adding libwebkitgtk and dependent libraries
directly to GUI_TK_LIBRARY.

This ensure that the core library doesn't have any dependencies on
libwebkitgtk which it doesn't need.

Closes #16624.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@78026 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

configure

@@ -923,6 +923,7 @@ DEBUG_FLAG
 DEBUG_INFO
 UNICODE
 WITH_PLUGIN_SDL
+EXTRALIBS_WEBVIEW
 EXTRALIBS_STC
 EXTRALIBS_SDL
 EXTRALIBS_OPENGL
@@ -26227,7 +26228,6 @@ $as_echo "none" >&6; }
         if `pkg-config --variable qt_config Qt5Core | grep "reduce_relocations" >/dev/null`; then
                         SAMPLES_CXXFLAGS="-fPIC $SAMPLES_CXXFLAGS"
             WXCONFIG_CXXFLAGS="-fPIC $WXCONFIG_CXXFLAGS $TOOLKIT_INCLUDE"
-            LDFLAGS=" $LDFLAGS -fPIE"
         fi
     fi
         TOOLKIT_DIR=`echo ${TOOLKIT} | tr '[A-Z]' '[a-z]'`
@@ -36419,7 +36419,7 @@ $as_echo "yes" >&6; }
 
                                 USE_WEBVIEW_WEBKIT=1
                                 CPPFLAGS="$CPPFLAGS $WEBKIT_CFLAGS"
-                                GUI_TK_LIBRARY="$GUI_TK_LIBRARY $WEBKIT_LIBS"
+                                EXTRALIBS_WEBVIEW="$WEBKIT_LIBS"
 
 fi
         elif test "$wxUSE_MAC" = 1 -a "$USE_DARWIN" = 1; then
@@ -37414,6 +37414,7 @@ fi
 
 
 
+
 
 
 TOOLKIT_LOWERCASE=`echo $TOOLKIT | tr '[A-Z]' '[a-z]'`