further reduce GUIBASE usage; don't set it to headless

Change-Id: I76916c15f380bd80e823845f52f32a1c444079da

configure.ac

@@ -3966,7 +3966,7 @@ if test "$enable_headless" = "yes"; then
     if test "$GUIBASE" != "unx"; then
         AC_MSG_ERROR([$host_os operating system is not suitable to build LibreOffice with --enable-headless])
     fi
-    GUIBASE=headless
+    GUIBASE=not-used
 fi
 
 INPATH="${OUTPATH}${PROEXT}"

desktop/Executable_oosplash.mk

@@ -35,15 +35,13 @@ $(eval $(call gb_Executable_add_libs,oosplash,\
 
 endif
 
-ifneq ($(GUIBASE),headless)
+ifneq ($(ENABLE_HEADLESS),TRUE)
+
 ifneq ($(OS),WNT)
 $(eval $(call gb_Executable_add_libs,oosplash,\
     -lX11 \
 ))
 endif
-endif
-
-ifneq ($(ENABLE_HEADLESS),TRUE)
 
 $(eval $(call gb_Executable_add_defs,oosplash,\
     -DENABLE_QUICKSTART_LIBPNG \

postprocess/Rdb_services.mk

@@ -145,7 +145,7 @@ $(eval $(call gb_Rdb_add_components,services,\
 			accessibility/bridge/org/openoffice/accessibility/java_uno_accessbridge \
 		) \
 	) \
-	$(if $(filter headless,$(GUIBASE)), \
+	$(if $(ENABLE_HEADLESS), \
 		vcl/vcl.headless \
 	) \
 	$(if $(filter-out WNT,$(OS)), \
@@ -295,7 +295,7 @@ $(eval $(call gb_Rdb_add_components,services,\
 	) \
 	$(if $(filter-out MACOSX WNT,$(OS)), \
 		desktop/unx/splash/splash \
-		$(if $(filter-out headless,$(GUIBASE)), \
+		$(if $(ENABLE_HEADLESS),, \
 			shell/source/backends/desktopbe/desktopbe1 \
 			vcl/vcl.unx \
 		) \

toolkit/Library_tk.mk

@@ -128,7 +128,7 @@ $(eval $(call gb_Library_add_cxxflags,tk,\
     $(gb_OBJCXXFLAGS)))
 endif
 
-ifneq ($(GUIBASE),headless)
+ifeq (,$(ENABLE_HEADLESS))
 ifneq (,$(filter LINUX DRAGONFLY OPENBSD FREEBSD NETBSD, $(OS)))
 $(eval $(call gb_Library_add_libs,tk,\
     -lX11 \

vcl/Library_vcl.mk

@@ -27,7 +27,7 @@ else ifeq ($(OS),ANDROID)
 $(eval $(call gb_Library_set_componentfile,vcl,vcl/vcl.android))
 else ifeq ($(OS),IOS)
 $(eval $(call gb_Library_set_componentfile,vcl,vcl/vcl.ios))
-else ifeq ($(GUIBASE),headless)
+else ifeq ($(ENABLE_HEADLESS),TRUE)
 $(eval $(call gb_Library_set_componentfile,vcl,vcl/vcl.headless))
 else
 $(eval $(call gb_Library_set_componentfile,vcl,vcl/vcl.unx))
@@ -324,12 +324,7 @@ $(eval $(call gb_Library_add_exception_objects,vcl,\
 ))
 
 # handle X11 platforms, which have additional files and possibly system graphite
-ifeq ($(GUIBASE),unx)
-$(eval $(call gb_Library_add_exception_objects,vcl,\
-    vcl/generic/glyphs/graphite_serverfont \
-))
-endif
-ifeq ($(GUIBASE),headless)
+ifneq (,$(or $(filter unx,$(GUIBASE)),$(ENABLE_HEADLESS)))
 $(eval $(call gb_Library_add_exception_objects,vcl,\
     vcl/generic/glyphs/graphite_serverfont \
 ))
@@ -538,7 +533,7 @@ $(eval $(call gb_Library_use_externals,vcl,\
 ))
 endif
 
-ifeq ($(GUIBASE),headless)
+ifeq ($(ENABLE_HEADLESS),TRUE)
 $(eval $(call gb_Library_add_defs,vcl,\
     -DSAL_DLLPREFIX=\"$(gb_Library_SYSPRE)\" \
     -DSAL_DLLPOSTFIX=\"$(gb_Library_OOOEXT)\" \