Make Null a public class of dart:core.

runtime/vm/flow_graph_builder.cc

Index: runtime/vm/flow_graph_builder.cc
diff --git a/runtime/vm/flow_graph_builder.cc b/runtime/vm/flow_graph_builder.cc
index e818aa2b1e9e5a553523ae2b07d102e33b3c7432..cfad845edad94b069e93aa03636cf1f9d00a4a20 100644
--- a/runtime/vm/flow_graph_builder.cc
+++ b/runtime/vm/flow_graph_builder.cc
@@ -1223,7 +1223,6 @@ void ValueGraphVisitor::BuildTypeTest(ComparisonNode* node) {
       type.IsInstantiated()) {
     const Instance& literal_value = node->left()->AsLiteralNode()->literal();
     ConstantInstr* result = NULL;
-

[regis, 2013/08/15 17:27:26]

Any particular reason to remove these 2 blank lines? Or is it just a not quite
reverted change?

[rmacnak, 2013/08/15 17:56:04]

No reason, just an artifact of merging with dart2js folks making the same
change.

     Error& malformed_error = Error::Handle();
     if (literal_value.IsInstanceOf(type,
                                    TypeArguments::Handle(),
@@ -1235,7 +1234,6 @@ void ValueGraphVisitor::BuildTypeTest(ComparisonNode* node) {
                                  Bool::True() : Bool::False());
     }
     ASSERT(malformed_error.IsNull());
-
     ReturnDefinition(result);
     return;
   }