Removed unused StandardTestSuite.cachedTests field

tools/testing/dart/test_suite.dart

Index: tools/testing/dart/test_suite.dart
diff --git a/tools/testing/dart/test_suite.dart b/tools/testing/dart/test_suite.dart
index 114a34afef6cb11d7b1db4235cfb8d0a6d5adac4..c16dfaf4860daccee92574283165b0a671ea6e42 100644
--- a/tools/testing/dart/test_suite.dart
+++ b/tools/testing/dart/test_suite.dart
@@ -406,7 +406,6 @@ class StandardTestSuite extends TestSuite {
   final List<String> statusFilePaths;
   TestCaseEvent doTest;
   TestExpectations testExpectations;
-  List<TestInformation> cachedTests;
   final Path dartDir;
   Predicate<String> isTestFilePredicate;
   final bool listRecursively;
@@ -502,7 +501,7 @@ class StandardTestSuite extends TestSuite {
       // Checked if we have already found and generated the tests for
       // this suite.
       if (!testCache.containsKey(suiteName)) {
-        cachedTests = testCache[suiteName] = [];
+        testCache[suiteName] = [];
         return enqueueTests();
       } else {
         // We rely on enqueueing completing asynchronously.
@@ -803,7 +802,6 @@ class StandardTestSuite extends TestSuite {
                                      isNegativeIfChecked,
                                      hasFatalTypeErrors,
                                      multitestOutcome);
-      cachedTests.add(info);
       enqueueTestCaseFromTestInformation(info);
     };
   }