Support StackTrace.current

tool/input_sdk/patch/core_patch.dart

Index: tool/input_sdk/patch/core_patch.dart
diff --git a/tool/input_sdk/patch/core_patch.dart b/tool/input_sdk/patch/core_patch.dart
index 549c5df7b3ba8589e339bde8e9f448927399ae48..d557375c54b5bf3662b5ce40c99891fcc627bc14 100644
--- a/tool/input_sdk/patch/core_patch.dart
+++ b/tool/input_sdk/patch/core_patch.dart
@@ -452,3 +452,24 @@ class Uri {
     throw new UnsupportedError("'Uri.base' is not supported");
   }
 }
+
+@patch
+class StackTrace {
+  @patch
+  @NoInline()

[Jennifer Messerly, 2016/02/19 22:23:56]

I think I've been removing these, they're meaningless to DDC

+  static StackTrace get current {
+    var error = JS('', 'new Error()');
+    var stack = JS('String|Null', '#.stack', error);
+    if (stack is String) return new StackTrace.fromString(stack);
+    if (JS('', 'Error.captureStackTrace') != null) {
+      JS('void', 'Error.captureStackTrace(#)', error);
+      var stack = JS('String|Null', '#.stack', error);
+      if (stack is String) return new StackTrace.fromString(stack);
+    }
+    try {
+      throw 0;
+    } catch (_, stackTrace) {
+      return stackTrace;
+    }
+  }
+}