make bspack not relying on c stubs so that it can be running without compiling

Author: bobzhang

jscomp/ext/ext_string.ml

@@ -332,7 +332,7 @@ let replace_backward_slash (x : string)=
 
 let empty = ""
 
-#if BS_BROWSER then
+#if BS_BROWSER || BS_PACK then
 let compare = Bs_hash_stubs.string_length_based_compare
 #else
 external compare : string -> string -> int = "caml_string_length_based_compare" [@@noalloc];;    

jscomp/ext/ext_string.mli

@@ -164,7 +164,7 @@ val replace_backward_slash : string -> string
 
 val empty : string 
 
-#if BS_BROWSER then
+#if BS_BROWSER || BS_PACK then
 val compare :  string -> string -> int
 #else
 external compare : string -> string -> int = "caml_string_length_based_compare" [@@noalloc];;  

jscomp/snapshot.ninja

@@ -48,7 +48,7 @@ build $SNAP/unstable/all_ounit_tests.ml: bspack | ./bin/bspack.exe $LTO
     main = Ounit_tests_main         
 
 build $SNAP/unstable/bspack.ml: bspack | ./bin/bspack.exe $LTO
-    flags = -bs-MD -module-alias Config=Config_whole_compiler  -I $OCAML_SRC_PARSING -I $OCAML_SRC_UTILS -I stubs -I ext -I common -I depends -I core -I main -bs-main Bspack_main
+    flags = -D BS_PACK=true -bs-MD -module-alias Config=Config_whole_compiler  -I $OCAML_SRC_PARSING -I $OCAML_SRC_UTILS -I stubs -I ext -I common -I depends -I core -I main -bs-main Bspack_main
     main = Bspack_main
 
 build $SNAP/unstable/js_compiler.ml: bspack | ./bin/bspack.exe $LTO

jscomp/stubs/bs_hash_stubs.ml

@@ -1,5 +1,5 @@
 
-#if BS_BROWSER then
+#if BS_BROWSER || BS_PACK then
 
 
 let hash_string : string -> int = Hashtbl.hash