[dart2js] Report an error if throw is used outside of catch expression without an argument.

lib/compiler/implementation/ssa/builder.dart

Index: lib/compiler/implementation/ssa/builder.dart
diff --git a/lib/compiler/implementation/ssa/builder.dart b/lib/compiler/implementation/ssa/builder.dart
index c3deabd100b724d52d9546d5d613a49114ed22b0..a1894b36b6bf62534de34cf9616597ac9e60fc89 100644
--- a/lib/compiler/implementation/ssa/builder.dart
+++ b/lib/compiler/implementation/ssa/builder.dart
@@ -3197,8 +3197,7 @@ class SsaBuilder extends ResolvedVisitor implements Visitor {
       HInstruction exception = rethrowableException;
       if (exception === null) {
         exception = graph.addConstantNull(constantSystem);
-        compiler.reportError(node,
-                             'throw without expression outside catch block');
+        compiler.internalError('rethrowableException should not be null', node);

[ahe, 2012/10/03 10:25:28]

I think you should use "node: node". I plan to make this method use the {}
syntax instead of the [] syntax.

[Roman, 2012/10/03 10:36:20]

Done.

       }
       close(new HThrow(exception, isRethrow: true));
     } else {