[cfe] Run suite in together in update_expectations.dart

This speeds up update_expectations.dart by avoid to restart
the expectation testing for each suite.

Change-Id: Idaeb1cff3ac861b6d4781a4166442a102c754c71
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/342586
Commit-Queue: Johnni Winther <johnniwinther@google.com>
Reviewed-by: Jens Johansen <jensj@google.com>
diff --git a/pkg/front_end/tool/update_expectations.dart b/pkg/front_end/tool/update_expectations.dart
index bed85ca..0c0c448 100644
--- a/pkg/front_end/tool/update_expectations.dart
+++ b/pkg/front_end/tool/update_expectations.dart
@@ -21,22 +21,23 @@
 Future<void> runStandardSuites([List<String>? args]) async {
   // Assert that 'strong' is the first suite - we use the assumption below.
   assert(standardSuites.first == 'weak', "Suite 'weak' most be the first.");
-  bool first = true;
+
+  List<String> testingArguments = [];
   for (String suite in standardSuites) {
     List<String> tests = args == null
         ? [suite]
         : args.map((String arg) => '${suite}/$arg').toList();
-    await fasta.main([
-      'testing',
-      ...tests,
-      // Only update comments in the first suite. Note that this only works
-      // if the first compilation is a full compilation, i.e. not outline,
-      // because comments are generated during body building and inference.
-      if (first) '-DupdateComments=true',
-      '-DupdateExpectations=true'
-    ]);
-    first = false;
+    testingArguments.addAll(tests);
   }
+  await fasta.main([
+    'testing',
+    ...testingArguments,
+    // Only update comments in the first suite. Note that this only works
+    // if the first compilation is a full compilation, i.e. not outline,
+    // because comments are generated during body building and inference.
+    '-DupdateComments=true',
+    '-DupdateExpectations=true'
+  ]);
 }
 
 Future<void> main(List<String> args) async {
@@ -61,7 +62,7 @@
       }
     }
     if (standardTests.isNotEmpty) {
-      await runStandardSuites(args);
+      await runStandardSuites(standardTests);
     }
   }
 }