Move CCodec_ModuleMgr ownership to CPDF_ModuleMgr.

More straight forward than CFX_GEModule owning in and CPDF_ModuleMgr
holding a pointer to it.

Remove assumptions that the codec modules may return nullptr, and do
IWYU.

Change-Id: Iba7fc3c7ec223fd6d29a1ab74ed13d35689bc5d5
Reviewed-on: https://pdfium-review.googlesource.com/5654
Commit-Queue: dsinclair <dsinclair@chromium.org>
Reviewed-by: dsinclair <dsinclair@chromium.org>
diff --git a/xfa/DEPS b/xfa/DEPS
index cc3061d..2dd4ef3 100644
--- a/xfa/DEPS
+++ b/xfa/DEPS
@@ -1,7 +1,5 @@
 include_rules = [
-  '+core/fpdfapi/parser',
-  '+core/fxcrt',
-  '+core/fxge',
+  '+core',
   '+fxbarcode',
   '+third_party/bigint'
 ]