Analyzer: add triple-shift constant test

Bug: #44908
Change-Id: If510a9aa36fa028e8f91d3cc9dd161282d2db383
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/184701
Reviewed-by: Brian Wilkerson <brianwilkerson@google.com>
Commit-Queue: Samuel Rawlins <srawlins@google.com>

pkg/analyzer/test/generated/constant_test.dart

@@ -5,6 +5,7 @@
 @deprecated
 library analyzer.test.constant_test;
 
+import 'package:analyzer/src/dart/analysis/experiments.dart';
 import 'package:analyzer/src/dart/element/element.dart';
 import 'package:analyzer/src/generated/constant.dart';
 import 'package:test/test.dart';
@@ -20,6 +21,18 @@ main() {
 
 @reflectiveTest
 class ConstantEvaluatorTest extends PubPackageResolutionTest {
+  @override
+  void setUp() {
+    super.setUp();
+    writeTestPackageAnalysisOptionsFile(
+      AnalysisOptionsFileConfig(
+        experiments: [
+          EnableString.triple_shift,
+        ],
+      ),
+    );
+  }
+
   test_bitAnd_int_int() async {
     await _assertValueInt(74 & 42, "74 & 42");
   }
@@ -446,6 +459,10 @@ const [for (var i = 0; i < 4; i++) i]
     await _assertValueInt(6, "2 * 3");
   }
 
+  test_tripleShift() async {
+    await _assertValueInt(16, "64 >>> 2");
+  }
+
   test_truncatingDivide_double_double() async {
     await _assertValueInt(1, "3.2 ~/ 2.3");
   }