Add accessor for getting target-specific constructor.

pkg/front_end/lib/src/fasta/kernel/body_builder.dart

Index: pkg/front_end/lib/src/fasta/kernel/body_builder.dart
diff --git a/pkg/front_end/lib/src/fasta/kernel/body_builder.dart b/pkg/front_end/lib/src/fasta/kernel/body_builder.dart
index 23f3a13d4882092cdbe9fa865752b00fe7df9590..a2357c1f0e2f243468e1271137e1a70a9301ca25 100644
--- a/pkg/front_end/lib/src/fasta/kernel/body_builder.dart
+++ b/pkg/front_end/lib/src/fasta/kernel/body_builder.dart
@@ -2202,13 +2202,11 @@ class BodyBuilder extends ScopeListener<JumpTarget> implements BuilderHelper {
   Expression buildCompileTimeError(error, [int charOffset = -1]) {
     String message = new InputError(uri, charOffset, error).format();
     print(message);
-    // TODO(ahe): Use a method on TargetImplementation for looking up the
-    // constructor.
-    final Constructor constructor = coreTypes.getCoreClass(
-        "dart:core", "_CompileTimeError").constructors.first;
-    return new Throw(new ConstructorInvocation(
-        constructor,
-        new Arguments(<Expression>[new StringLiteral(message)])));
+    Builder constructor = library.loader.getCompileTimeError();
+    return new Throw(
+        buildStaticInvocation(constructor.target,
+            new Arguments(<Expression>[new StringLiteral(message)]),
+            isConst: false)); // TODO(ahe): Make this const.
   }
 
   Statement buildCompileTimeErrorStatement(error, [int charOffset = -1]) {