Print the isolate's sticky error if it has one.

runtime/observatory/tests/service/get_version_rpc_test.dart

Index: runtime/observatory/tests/service/get_version_rpc_test.dart
diff --git a/runtime/observatory/tests/service/get_version_rpc_test.dart b/runtime/observatory/tests/service/get_version_rpc_test.dart
index d4c49135fa4d9fb68eaae1023ed69d95c7d4d9bf..5bae8816b3fa84e4ab7bb8b4a1e1e74d8de4cbae 100644
--- a/runtime/observatory/tests/service/get_version_rpc_test.dart
+++ b/runtime/observatory/tests/service/get_version_rpc_test.dart
@@ -13,7 +13,7 @@ var tests = [
     var result = await vm.invokeRpcNoUpgrade('getVersion', {});
     expect(result['type'], equals('Version'));
     expect(result['major'], equals(3));
-    expect(result['minor'], equals(3));
+    expect(result['minor'], equals(4));
     expect(result['_privateMajor'], equals(0));
     expect(result['_privateMinor'], equals(0));
   },