Add operators test to source_mapping_test.

pkg/compiler/lib/src/ssa/codegen.dart

Index: pkg/compiler/lib/src/ssa/codegen.dart
diff --git a/pkg/compiler/lib/src/ssa/codegen.dart b/pkg/compiler/lib/src/ssa/codegen.dart
index 6057d6f42e863dc7db5cadaf37af619a2a82f30b..998ed3659b960fef0607defa01649abe4011f5cf 100644
--- a/pkg/compiler/lib/src/ssa/codegen.dart
+++ b/pkg/compiler/lib/src/ssa/codegen.dart
@@ -1911,8 +1911,12 @@ class SsaCodeGenerator implements HVisitor, HBlockInformationVisitor {
         registry.registerTypeConstant(element);
       }
     }
-    push(backend.emitter.constantReference(constant)
-            .withSourceInformation(sourceInformation));
+    js.Expression expression = backend.emitter.constantReference(constant);
+    if (!constant.isDummy) {
+      // TODO(johnniwinther): Support source information on synthetic constants.
+      expression = expression.withSourceInformation(sourceInformation);
+    }
+    push(expression);
   }
 
   visitConstant(HConstant node) {
@@ -2709,7 +2713,9 @@ class SsaCodeGenerator implements HVisitor, HBlockInformationVisitor {
       js.Statement body = new js.Block.empty();
       currentContainer = body;
       if (node.isArgumentTypeCheck) {
-        generateThrowWithHelper('iae', node.checkedInput);
+        generateThrowWithHelper('iae',
+            node.checkedInput,
+            sourceInformation: node.sourceInformation);
       } else if (node.isReceiverTypeCheck) {
         use(node.checkedInput);
         js.Name methodName =
@@ -2859,4 +2865,9 @@ class SsaCodeGenerator implements HVisitor, HBlockInformationVisitor {
     registry.registerStaticUse(helper);
     return backend.emitter.staticFunctionAccess(helper);
   }
+
+  @override
+  void visitRef(HRef node) {
+    visit(node.value);
+  }
 }