Move xfa_document to cxfa_document

BUILD.gn

Index: BUILD.gn
diff --git a/BUILD.gn b/BUILD.gn
index cbe95ee6dd2ff02c1b1b8b67df7d4a289150d13a..648364234a7f575072badd732075d1d5c8ce6970 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -1370,6 +1370,8 @@ if (pdf_enable_xfa) {
       "xfa/fxfa/parser/cxfa_corner.h",
       "xfa/fxfa/parser/cxfa_data.cpp",
       "xfa/fxfa/parser/cxfa_data.h",
+      "xfa/fxfa/parser/cxfa_document.cpp",
+      "xfa/fxfa/parser/cxfa_document.h",
       "xfa/fxfa/parser/cxfa_document_parser.cpp",
       "xfa/fxfa/parser/cxfa_document_parser.h",
       "xfa/fxfa/parser/cxfa_edge.h",
@@ -1441,10 +1443,8 @@ if (pdf_enable_xfa) {
       "xfa/fxfa/parser/xfa_basic_data_element_script.cpp",
       "xfa/fxfa/parser/xfa_basic_data_enum.cpp",
       "xfa/fxfa/parser/xfa_basic_data_packets.cpp",
-      "xfa/fxfa/parser/xfa_document.h",
       "xfa/fxfa/parser/xfa_document_datamerger_imp.cpp",
       "xfa/fxfa/parser/xfa_document_datamerger_imp.h",
-      "xfa/fxfa/parser/xfa_document_imp.cpp",
       "xfa/fxfa/parser/xfa_document_serialize.cpp",
       "xfa/fxfa/parser/xfa_document_serialize.h",
       "xfa/fxfa/parser/xfa_layout_appadapter.cpp",