Remove --harmony-modules flag and let embedder decide when modules are used

src/d8.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 
 // Defined when linking against shared lib on Windows.
 #if defined(USING_V8_SHARED) && !defined(V8_SHARED)
 #define V8_SHARED
 #endif
 
@@ skipping 1965 matching lines @@
       } else {
         printf("Unknown option to --cache.\n");
         return false;
       }
       argv[i] = NULL;
     }
   }
 
   v8::V8::SetFlagsFromCommandLine(&argc, argv, true);
 
-  bool enable_harmony_modules = false;

[Dan Ehrenberg, 2016/03/15 00:22:52]

Presumably there's no reasonable way to recover the module functionality at d8,
right? Because how would you collect the exports, and where would they go? Or
could we allow it but in a special mode where exports are banned?

[adamk, 2016/03/15 00:40:58]

Not sure what you mean...d8 does support modules. As per the comment below, it's
just handled in a different function. The following loads a file as a module:

d8 --module foo.js

At the moment imports don't work, but I have some basic tests in
mjsunit/harmony/modules.js

-
   // Set up isolated source groups.
   options.isolate_sources = new SourceGroup[options.num_isolates];
   SourceGroup* current = options.isolate_sources;
   current->Begin(argv, 1);
   for (int i = 1; i < argc; i++) {
     const char* str = argv[i];
     if (strcmp(str, "--isolate") == 0) {
       current->End(i);
       current++;
       current->Begin(argv, i + 1);
     } else if (strcmp(str, "--module") == 0) {
       // Pass on to SourceGroup, which understands this option.
-      enable_harmony_modules = true;
     } else if (strncmp(argv[i], "--", 2) == 0) {
       printf("Warning: unknown flag %s.\nTry --help for options\n", argv[i]);
     } else if (strcmp(str, "-e") == 0 && i + 1 < argc) {
       options.script_executed = true;
     } else if (strncmp(str, "-", 1) != 0) {
       // Not a flag, so it must be a script to execute.
       options.script_executed = true;
     }
   }
   current->End(argc);
 
   if (!logfile_per_isolate && options.num_isolates) {
     SetFlagsFromString("--nologfile_per_isolate");
   }
 
-  if (enable_harmony_modules) {
-    SetFlagsFromString("--harmony-modules");
-  }
-
   return true;
 }
 
 
 int Shell::RunMain(Isolate* isolate, int argc, char* argv[], bool last_run) {
 #ifndef V8_SHARED
   for (int i = 1; i < options.num_isolates; ++i) {
     options.isolate_sources[i].StartExecuteInThread();
   }
 #endif  // !V8_SHARED
@@ skipping 510 matching lines @@
 }
 
 }  // namespace v8
 
 
 #ifndef GOOGLE3
 int main(int argc, char* argv[]) {
   return v8::Shell::Main(argc, argv);
 }
 #endif