Restrict fxcrt's visibility to third_party.

Change-Id: I4b4b1a8e78e2405791aca915e4d48a88e79444d5
Reviewed-on: https://pdfium-review.googlesource.com/c/43993
Commit-Queue: Lei Zhang <thestig@chromium.org>
Reviewed-by: Tom Sepez <tsepez@chromium.org>
diff --git a/core/fxcrt/BUILD.gn b/core/fxcrt/BUILD.gn
index 170d4d0..3a38520 100644
--- a/core/fxcrt/BUILD.gn
+++ b/core/fxcrt/BUILD.gn
@@ -89,7 +89,10 @@
     "../../fpdfsdk/*",
     "../../fxbarcode:*",
     "../../fxjs:*",
-    "../../third_party:*",
+    "../../third_party:fx_agg",
+    "../../third_party:fx_lcms2",
+    "../../third_party:fx_tiff",
+    "../../third_party:pdfium_base",
     "../../xfa/*",
   ]
   deps = [
@@ -100,6 +103,8 @@
     "../../third_party:pdfium_base",
     "//third_party/icu:icuuc",
   ]
+  allow_circular_includes_from = [ "../../third_party:pdfium_base" ]
+
   if (is_posix || is_fuchsia) {
     sources += [
       "cfx_fileaccess_posix.cpp",
diff --git a/third_party/BUILD.gn b/third_party/BUILD.gn
index a9a59ce..7a5a6c3 100644
--- a/third_party/BUILD.gn
+++ b/third_party/BUILD.gn
@@ -287,6 +287,9 @@
     "lcms/src/cmswtpnt.c",
     "lcms/src/cmsxform.c",
   ]
+  deps = [
+    "../core/fxcrt",
+  ]
 }
 
 if (!build_with_chromium) {
@@ -494,6 +497,7 @@
     }
     deps = [
       ":zlib",
+      "../core/fxcrt",
       "//third_party:jpeg",
     ]
     sources = [