Make compile-time errors catchable

runtime/vm/exceptions.cc

Index: runtime/vm/exceptions.cc
diff --git a/runtime/vm/exceptions.cc b/runtime/vm/exceptions.cc
index 37a99f25dcae5330f9ae9ccad548e67247c7825b..f645cb9d346699530c4a8b105e46019689455ca8 100644
--- a/runtime/vm/exceptions.cc
+++ b/runtime/vm/exceptions.cc
@@ -640,6 +640,13 @@ void Exceptions::ThrowRangeError(const char* argument_name,
 }
 
 
+void Exceptions::ThrowSyntaxError(const LanguageError& error) {
+  const Array& args = Array::Handle(Array::New(1));
+  args.SetAt(0, String::Handle(error.FormatMessage()));
+  Exceptions::ThrowByType(Exceptions::kSyntaxError, args);
+}
+
+
 RawObject* Exceptions::Create(ExceptionType type, const Array& arguments) {
   Library& library = Library::Handle();
   const String* class_name = NULL;
@@ -713,6 +720,10 @@ RawObject* Exceptions::Create(ExceptionType type, const Array& arguments) {
     case kCyclicInitializationError:
       library = Library::CoreLibrary();
       class_name = &Symbols::CyclicInitializationError();
+      break;
+    case kSyntaxError:
+      library = Library::CoreLibrary();
+      class_name = &Symbols::SyntaxError();

[siva, 2016/09/15 18:11:45]

Does this need to be
  break;

default:
  UNREACHABLE();

like the way we do in other switch statements?

[hausner, 2016/09/15 21:28:28]

Done.

There does not seem to be a default case, though.

   }
 
   return DartLibraryCalls::InstanceCreate(library,