Add operators test to source_mapping_test.

pkg/compiler/lib/src/cps_ir/cps_ir_nodes.dart

Index: pkg/compiler/lib/src/cps_ir/cps_ir_nodes.dart
diff --git a/pkg/compiler/lib/src/cps_ir/cps_ir_nodes.dart b/pkg/compiler/lib/src/cps_ir/cps_ir_nodes.dart
index 8c5bf34b55f808e940905dfae91c7e40c761d332..c865877aaa3cc9c47521d0945a0fe7f0e6cfc2d0 100644
--- a/pkg/compiler/lib/src/cps_ir/cps_ir_nodes.dart
+++ b/pkg/compiler/lib/src/cps_ir/cps_ir_nodes.dart
@@ -100,6 +100,10 @@ abstract class Primitive extends Definition<Primitive> {
   /// True if time-of-evaluation is irrelevant for the given primitive,
   /// assuming its inputs are the same values.
   bool get isSafeForReordering;
+
+  /// The source information associated with this primitive.
+  // TODO(johnniwinther): Require source information for all primitives.
+  SourceInformation get sourceInformation => null;
 }
 
 /// Operands to invocations and primitives are always variables.  They point to
@@ -325,7 +329,7 @@ class InvokeMethod extends Expression implements Invoke {
                            this.mask,
                            this.arguments,
                            this.continuation,
-                           [this.sourceInformation]);
+                           this.sourceInformation);
 
   accept(Visitor visitor) => visitor.visitInvokeMethod(this);
 }
@@ -476,8 +480,11 @@ class TypeCast extends Expression {
 class ApplyBuiltinOperator extends Primitive {
   BuiltinOperator operator;
   List<Reference<Primitive>> arguments;
+  final SourceInformation sourceInformation;
 
-  ApplyBuiltinOperator(this.operator, List<Primitive> arguments)
+  ApplyBuiltinOperator(this.operator,
+                       List<Primitive> arguments,
+                       this.sourceInformation)
       : this.arguments = _referenceList(arguments);
 
   accept(Visitor visitor) => visitor.visitApplyBuiltinOperator(this);
@@ -833,7 +840,9 @@ class CreateInstance extends Primitive {
 class Interceptor extends Primitive {
   final Reference<Primitive> input;
   final Set<ClassElement> interceptedClasses;
-  Interceptor(Primitive input, this.interceptedClasses)
+  final SourceInformation sourceInformation;
+
+  Interceptor(Primitive input, this.interceptedClasses, this.sourceInformation)
       : this.input = new Reference<Primitive>(input);
   accept(Visitor visitor) => visitor.visitInterceptor(this);