Dart2js option to dump info about compilation

sdk/lib/_internal/compiler/implementation/js_emitter/code_emitter_task.dart

Index: sdk/lib/_internal/compiler/implementation/js_emitter/code_emitter_task.dart
diff --git a/sdk/lib/_internal/compiler/implementation/js_emitter/code_emitter_task.dart b/sdk/lib/_internal/compiler/implementation/js_emitter/code_emitter_task.dart
index ac52424185f11ffced91faac42810a47d313674e..07e4099bf1a460e271d1de026b7e703210bf7c49 100644
--- a/sdk/lib/_internal/compiler/implementation/js_emitter/code_emitter_task.dart
+++ b/sdk/lib/_internal/compiler/implementation/js_emitter/code_emitter_task.dart
@@ -1163,6 +1163,7 @@ mainBuffer.add(r'''
 
       jsAst.ObjectInitializer initializers =
           descriptor.toObjectInitializer();
+      int sizeBefore = outputBuffers[outputUnit].length;

[ngeoffray, 2013/12/05 09:29:28]

Why isn't the element visitor enough to know the full size of the library?

[sigurdm, 2013/12/05 11:35:03]

The code for the library looks like:

["", "simple.dart", , M, {
  foo1: function(a, c, f) {
    var i;
    for (i = 0; i < 10; ++i)
      a = C.JSString_methods.$add(a, new M.foo1_closure().call$1(10 + i));
    return new M.foo1_closure0();
  },
[[ snip ]]
  foo1__closure0: {
    "": "Closure;",
    call$0: function() {
      P.print($.b);
    }
  }
},
1]

So there are some bytes that are "boiler-plate" - not directly belonging to any
member

       outputBuffers[outputUnit]
           ..write('["${library.getLibraryName()}",$_')
           ..write('"${uri}",$_')
@@ -1174,6 +1175,9 @@ mainBuffer.add(r'''
           ..write(jsAst.prettyPrint(initializers, compiler))
           ..write(library == compiler.mainApp ? ',${n}1' : "")
           ..write('],$n');
+      int sizeAfter = outputBuffers[outputUnit].length;
+      compiler.dumpInfoTask.codeSizeCounter
+          .countCode(library, sizeAfter - sizeBefore);
     }
   }