Extract 'computeLineStarts' utility.

pkg/analyzer/test/generated/test_all.dart

Index: pkg/analyzer/test/generated/test_all.dart
diff --git a/pkg/analyzer/test/generated/test_all.dart b/pkg/analyzer/test/generated/test_all.dart
index fb84d461cafc2cb3e2308d946bf4b7d726f626dd..706967e799e7cc6befb82976441d8b71498fcd64 100644
--- a/pkg/analyzer/test/generated/test_all.dart
+++ b/pkg/analyzer/test/generated/test_all.dart
@@ -24,6 +24,7 @@ import 'source_factory_test.dart' as source_factory_test;
 import 'static_type_warning_code_test.dart' as static_type_warning_code_test;
 import 'static_warning_code_test.dart' as static_warning_code_test;
 import 'type_system_test.dart' as type_system_test;
+import 'utilities_string_test.dart' as utilities_string_test;
 import 'utilities_test.dart' as utilities_test;
 
 /// Utility for manually running all tests.
@@ -47,6 +48,7 @@ main() {
     static_type_warning_code_test.main();
     static_warning_code_test.main();
     type_system_test.main();
+    utilities_string_test.main();
     utilities_test.main();
   });
 }