pdfium: re-enable PCH

Change-Id: I5987fcc04396e4e22640d6b09b52fa7b08460369
Reviewed-on: https://gerrit.libreoffice.org/72687Reviewed-by: Miklos Vajna <vmiklos@collabora.com>
Tested-by: Jenkins

external/pdfium/Library_pdfium.mk

@@ -13,8 +13,7 @@ $(eval $(call gb_Library_use_unpacked,pdfium,pdfium))
 
 $(eval $(call gb_Library_set_warnings_not_errors,pdfium))
 
-# FIXME this needs updating
-#$(eval $(call gb_Library_set_precompiled_header,pdfium,$(SRCDIR)/external/pdfium/inc/pch/precompiled_pdfium))
+$(eval $(call gb_Library_set_precompiled_header,pdfium,$(SRCDIR)/external/pdfium/inc/pch/precompiled_pdfium))
 
 $(eval $(call gb_Library_set_include,pdfium,\
     -I$(call gb_UnpackedTarball_get_dir,pdfium) \

external/pdfium/inc/pch/precompiled_pdfium.hxx

@@ -13,7 +13,7 @@
  manual changes will be rewritten by the next run of update_pch.sh (which presumably
  also fixes all possible problems, so it's usually better to use it).
 
- Generated on 2019-05-18 14:23:38 using:
+ Generated on 2019-05-21 17:15:06 using:
  ./bin/update_pch external/pdfium pdfium --cutoff=1 --exclude:system --include:module --include:local
 
  If after updating build fails, use the following command to locate conflicting headers:
@@ -124,7 +124,6 @@
 #include <core/fpdfapi/page/cpdf_pagemodule.h>
 #include <core/fpdfapi/page/cpdf_pageobject.h>
 #include <core/fpdfapi/page/cpdf_pageobjectholder.h>
-#include <core/fpdfapi/page/cpdf_pageobjectlist.h>
 #include <core/fpdfapi/page/cpdf_path.h>
 #include <core/fpdfapi/page/cpdf_pathobject.h>
 #include <core/fpdfapi/page/cpdf_pattern.h>