Fix BUILD.gn for commit 3522876d.

TBR=palmer@chromium.org

Review URL: https://codereview.chromium.org/378073002
diff --git a/BUILD.gn b/BUILD.gn
index 43b7049..7f5c821 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -525,7 +525,6 @@
     "core/src/fxcrt/fx_basic_list.cpp",
     "core/src/fxcrt/fx_basic_maps.cpp",
     "core/src/fxcrt/fx_basic_memmgr.cpp",
-    "core/src/fxcrt/fx_basic_memmgr_mini.cpp",
     "core/src/fxcrt/fx_basic_plex.cpp",
     "core/src/fxcrt/fx_basic_utf.cpp",
     "core/src/fxcrt/fx_basic_util.cpp",
@@ -535,7 +534,6 @@
     "core/src/fxcrt/fx_unicode.cpp",
     "core/src/fxcrt/fx_xml_composer.cpp",
     "core/src/fxcrt/fx_xml_parser.cpp",
-    "core/src/fxcrt/mem_int.h",
     "core/src/fxcrt/plex.h",
     "core/src/fxcrt/xml_int.h",
   ]