Add an API function to get a debugger stack trace from an error handle.

tools/dom/src/native_DOMImplementation.dart

Index: tools/dom/src/native_DOMImplementation.dart
diff --git a/tools/dom/src/native_DOMImplementation.dart b/tools/dom/src/native_DOMImplementation.dart
index 43d542f8fe68b569add11d691992f67016feca1e..f0706fe14d835722e8b21a3901e7d93c27a898e7 100644
--- a/tools/dom/src/native_DOMImplementation.dart
+++ b/tools/dom/src/native_DOMImplementation.dart
@@ -70,24 +70,6 @@ class _Utils {
     return result;
   }
 
-  static List parseStackTrace(StackTrace stackTrace) {
-    final regExp = new RegExp(r'#\d\s+(.*) \((.*):(\d+):(\d+)\)');
-    List result = [];
-    for (var match in regExp.allMatches(stackTrace.toString())) {
-      result.add([match.group(1), match.group(2), int.parse(match.group(3)), int.parse(match.group(4))]);
-    }
-    return result;
-  }
-
-  static List captureParsedStackTrace() {
-    try {
-      // Throwing an exception is the only way to generate a stack trace.
-      throw new Exception();
-    } catch (e, stackTrace) {
-      return parseStackTrace(stackTrace);
-    }
-  }
-
   static void populateMap(Map result, List list) {
     for (int i = 0; i < list.length; i += 2) {
       result[list[i]] = list[i + 1];