Back enum class CPDF_SyntaxParser::ParseType with a bool.

Since it only has 2 values.

Change-Id: I28458662da7eda98602fdbbb7119eaac8ab09ea1
Reviewed-on: https://pdfium-review.googlesource.com/c/pdfium/+/85990
Commit-Queue: Lei Zhang <thestig@chromium.org>
Reviewed-by: Hui Yingst <nigi@chromium.org>

core/fpdfapi/parser/cpdf_syntax_parser.h

diff --git a/core/fpdfapi/parser/cpdf_syntax_parser.h b/core/fpdfapi/parser/cpdf_syntax_parser.h
index f8425f6..b7bcecd 100644
--- a/core/fpdfapi/parser/cpdf_syntax_parser.h
+++ b/core/fpdfapi/parser/cpdf_syntax_parser.h
@@ -29,7 +29,7 @@
 
 class CPDF_SyntaxParser {
  public:
-  enum class ParseType { kStrict, kLoose };
+  enum class ParseType : bool { kStrict, kLoose };
 
   struct WordResult {
     ByteString word;