Avoid passing a null uri to translateUri.

lib/compiler/implementation/apiimpl.dart

Index: lib/compiler/implementation/apiimpl.dart
diff --git a/lib/compiler/implementation/apiimpl.dart b/lib/compiler/implementation/apiimpl.dart
index 2296e262de0376aa22e3806ea4f0cdbbf117dc60..fc849c19da8a64b200dbb428009af2b80a4e89e6 100644
--- a/lib/compiler/implementation/apiimpl.dart
+++ b/lib/compiler/implementation/apiimpl.dart
@@ -96,7 +96,7 @@ class Compiler extends leg.Compiler {
   }
 
   void reportDiagnostic(leg.SourceSpan span, String message, bool fatal) {
-    if (span === null) {
+    if (span === null || span.uri === null) {

[ahe, 2012/06/22 08:49:33]

I would rather avoid creating source spans with uri == null. It is done in a few
places and should be easy to change to using null.

[Johnni Winther, 2012/06/22 11:40:55]

Done.

       handler(null, null, null, message, fatal);
     } else {
       handler(translateUri(span.uri, null), span.begin, span.end,