Changed generated code deps to avoid deps on core libraries.

This will allow the core libraries to be visibility controlled if
necessary.
diff --git a/BUILD b/BUILD
index 6b51ef5..442bab8 100644
--- a/BUILD
+++ b/BUILD
@@ -137,7 +137,9 @@
 cc_library(
     name = "generated_code_support__only_for_generated_code_do_not_use__i_give_permission_to_break_me",
     hdrs = [
+        "upb/decode.h",
         "upb/decode_fast.h",
+        "upb/encode.h",
         "upb/msg.h",
         "upb/msg_internal.h",
         "upb/port_def.inc",
@@ -151,6 +153,22 @@
     ],
 )
 
+cc_library(
+    name = "generated_reflection_support__only_for_generated_code_do_not_use__i_give_permission_to_break_me",
+    hdrs = [
+        "upb/def.h",
+        "upb/port_def.inc",
+        "upb/port_undef.inc",
+    ],
+    copts = UPB_DEFAULT_COPTS,
+    visibility = ["//visibility:public"],
+    deps = [
+        ":descriptor_upb_proto",
+        ":reflection",
+        ":table",
+    ],
+)
+
 upb_proto_library(
     name = "descriptor_upb_proto",
     visibility = ["//visibility:public"],