Address additional analysis issues in the observatory codebase.

runtime/observatory/tests/service/service_test_common.dart

Index: runtime/observatory/tests/service/service_test_common.dart
diff --git a/runtime/observatory/tests/service/service_test_common.dart b/runtime/observatory/tests/service/service_test_common.dart
index c623234c8165016393e895513e728fa59395f8e2..1bd7250004f9380d9795779425cc925f61eb2606 100644
--- a/runtime/observatory/tests/service/service_test_common.dart
+++ b/runtime/observatory/tests/service/service_test_common.dart
@@ -5,7 +5,8 @@
 library service_test_common;
 
 import 'dart:async';
-import 'dart:io' show Platform;
+import 'dart:io' show File, Platform;
+
 import 'package:observatory/models.dart' as M;
 import 'package:observatory/service_common.dart';
 import 'package:unittest/unittest.dart';
@@ -15,6 +16,29 @@ typedef Future VMTest(VM vm);
 
 Map<String, StreamSubscription> streamSubscriptions = {};
 
+class ScriptLineParser {

[rmacnak, 2017/06/12 16:02:12]

Awesome!

+  List<String> lines;
+
+  ScriptLineParser(Uri scriptUri) {
+    String content = new File(scriptUri.toFilePath()).readAsStringSync();
+    lines = content.split('\n');
+  }
+
+  int lineFor(String commentContent) {
+    String match1 = '// $commentContent';
+    String match2 = '/* $commentContent */';
+
+    for (int i = 0; i < lines.length; i++) {
+      if (lines[i].contains(match1) || lines[i].contains(match2)) {
+        // return the 1-based line number
+        return i + 1;
+      }
+    }
+
+    return -1;
+  }
+}
+
 Future subscribeToStream(VM vm, String streamName, onEvent) async {
   assert(streamSubscriptions[streamName] == null);