Make a couple more source_sets into jumbo_source_sets.

BUG=pdfium:964

Change-Id: I31c8e99ef35227404091c9c8e8f39a893eaf5b6b
Reviewed-on: https://pdfium-review.googlesource.com/c/43891
Reviewed-by: Henrique Nakashima <hnakashima@chromium.org>
Commit-Queue: Lei Zhang <thestig@chromium.org>
diff --git a/BUILD.gn b/BUILD.gn
index 2171d14..d91c92b 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -293,7 +293,7 @@
   "//:gn_visibility",
 ]
 
-source_set("constants") {
+jumbo_source_set("constants") {
   sources = [
     "constants/form_flags.h",
     "constants/page_object.h",
@@ -3089,7 +3089,7 @@
 }
 
 if (pdf_is_standalone) {
-  source_set("samples") {
+  jumbo_source_set("samples") {
     testonly = true
     deps = [
       "//samples",