Dart2js option to dump info about compilation

sdk/lib/_internal/compiler/implementation/dart2js.dart

Index: sdk/lib/_internal/compiler/implementation/dart2js.dart
diff --git a/sdk/lib/_internal/compiler/implementation/dart2js.dart b/sdk/lib/_internal/compiler/implementation/dart2js.dart
index 42a4056e665fa48fbd531fead9c4cdbe955e9dc3..045e1a434de2aab758a3f4d6050a1c096d985884 100644
--- a/sdk/lib/_internal/compiler/implementation/dart2js.dart
+++ b/sdk/lib/_internal/compiler/implementation/dart2js.dart
@@ -282,6 +282,7 @@ Future compile(List<String> argv) {
     new OptionHandler('--global-js-name=.*', checkGlobalName),
     new OptionHandler('--disable-type-inference', passThrough),
     new OptionHandler('--terse', passThrough),
+    new OptionHandler('--dump-info', passThrough),
     new OptionHandler('--disallow-unsafe-eval',
                       (_) => hasDisallowUnsafeEval = true),
     new OptionHandler('-D.+=.*', addInEnvironment),
@@ -366,6 +367,9 @@ Future compile(List<String> argv) {
             " \"Content-Security-Policy: script-src 'self'\"");
       } else if (extension == 'js.map' || extension == 'dart.map') {
         uri = sourceMapOut;
+      } else if (extension == 'info.html') {
+        String outName = out.path.substring(out.path.lastIndexOf('/') + 1);
+        uri = out.resolve('${outName}.$extension');
       } else {
         fail('Error: Unknown extension: $extension');
       }
@@ -576,6 +580,10 @@ be removed in a future version:
     variable named "$".  The name of this global can be overridden
     with this option.  The name must match the regular expression "\$[a-z]*".
 
+  --dump-info
+    Given this option dart2js generates a out.info.html file with information

[ahe, 2013/11/27 18:01:31]

"Given this option dart2js ..." is redundant.

[sigurdm, 2013/11/29 10:39:37]

Done.

[sigurdm, 2013/11/29 10:39:37]

Done.

+    about the generated code.
+
 '''.trim());
 }