Split off CPDF_Parser and CPDF_SimpleParser into .h/.cpp files

BUILD.gn

Index: BUILD.gn
diff --git a/BUILD.gn b/BUILD.gn
index 06f33a72b76764076bb3e92a6da35d53e8f1f26d..78baeef753b15e15a80dd8aad5cd73d7fad6d93f 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -238,6 +238,8 @@ static_library("fpdfdoc") {
 static_library("fpdfapi") {
   sources = [
     "core/include/fpdfapi/cpdf_document.h",
+    "core/include/fpdfapi/cpdf_parser.h",
+    "core/include/fpdfapi/cpdf_simple_parser.h",
     "core/include/fpdfapi/fpdf_module.h",
     "core/include/fpdfapi/fpdf_objects.h",
     "core/include/fpdfapi/fpdf_page.h",
@@ -333,6 +335,8 @@ static_library("fpdfapi") {
     "core/src/fpdfapi/fpdf_page/fpdf_page_pattern.cpp",
     "core/src/fpdfapi/fpdf_page/pageint.h",
     "core/src/fpdfapi/fpdf_parser/cpdf_document.cpp",
+    "core/src/fpdfapi/fpdf_parser/cpdf_parser.cpp",
+    "core/src/fpdfapi/fpdf_parser/cpdf_simple_parser.cpp",
     "core/src/fpdfapi/fpdf_parser/cpdf_syntax_parser.cpp",
     "core/src/fpdfapi/fpdf_parser/cpdf_syntax_parser.h",
     "core/src/fpdfapi/fpdf_parser/fpdf_parser_decode.cpp",
@@ -341,6 +345,7 @@ static_library("fpdfapi") {
     "core/src/fpdfapi/fpdf_parser/fpdf_parser_objects.cpp",
     "core/src/fpdfapi/fpdf_parser/fpdf_parser_parser.cpp",
     "core/src/fpdfapi/fpdf_parser/fpdf_parser_utility.cpp",
+    "core/src/fpdfapi/fpdf_parser/fpdf_parser_utility.h",
     "core/src/fpdfapi/fpdf_parser/parser_int.h",
     "core/src/fpdfapi/fpdf_render/fpdf_render.cpp",
     "core/src/fpdfapi/fpdf_render/fpdf_render_cache.cpp",