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 84101f43113969182d0e1c985f1de5f7582dc67d..d6e3e60d965c5568f4008d33add520a41b3c3b3d 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",
@@ -1423,10 +1428,10 @@ test("pdfium_unittests") {
     "core/src/fpdfapi/fpdf_font/fpdf_font_cid_unittest.cpp",
     "core/src/fpdfapi/fpdf_font/fpdf_font_unittest.cpp",
     "core/src/fpdfapi/fpdf_page/fpdf_page_parser_old_unittest.cpp",
+    "core/src/fpdfapi/fpdf_parser/cpdf_simple_parser_unittest.cpp",
     "core/src/fpdfapi/fpdf_parser/fpdf_parser_decode_unittest.cpp",
     "core/src/fpdfapi/fpdf_parser/fpdf_parser_objects_unittest.cpp",
     "core/src/fpdfapi/fpdf_parser/fpdf_parser_parser_unittest.cpp",
-    "core/src/fpdfapi/fpdf_parser/fpdf_parser_utility_unittest.cpp",
     "core/src/fpdfdoc/doc_basic_unittest.cpp",
     "core/src/fpdftext/fpdf_text_int_unittest.cpp",
     "core/src/fxcodec/codec/fx_codec_jpx_unittest.cpp",