Don't add the catch frame at a rethrow to the stacktrace.

tests/language/stacktrace_rethrow_error_test.dart

+// Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+class SubclassOfError extends Error {}
+
+fail() => throw "Fail";
+
+// == Rethrow, skipping through typed handlers. ==
+
+aa1() {
+  try {
+    bb1();
+    fail();
+  } catch(error
+          , stacktrace  /// withtraceparameter: ok
+          ) {
+    expectTrace(['gg1', 'ff1', 'ee1', 'dd1', 'cc1', 'bb1', 'aa1'], error.stackTrace);
+    expectTrace(['gg1', 'ff1', 'ee1', 'dd1', 'cc1', 'bb1', 'aa1'], stacktrace);  /// withtraceparameter: continued
+  }
+}
+
+bb1() => cc1();
+
+cc1() {
+  try {
+    dd1();
+  } on String catch(e) {
+    fail();
+  } on int catch(e) {
+    fail();
+  }
+}
+
+dd1() => ee1();
+
+ee1() {
+  try {
+    ff1();
+  } catch(e) {
+    rethrow;
+  }
+}
+
+ff1() => gg1();
+
+gg1() => throw new SubclassOfError();
+
+// == Rethrow, rethrow again in typed handler. ==
+
+aa2() {
+  try {
+    bb2();
+    fail();
+  } catch(error
+          , stacktrace  /// withtraceparameter: continued
+          ) {
+    expectTrace(['gg2', 'ff2', 'ee2', 'dd2', 'cc2', 'bb2', 'aa2'], error.stackTrace);
+    expectTrace(['gg2', 'ff2', 'ee2', 'dd2', 'cc2', 'bb2', 'aa2'], stacktrace);  /// withtraceparameter: continued
+  }
+}
+
+bb2() => cc2();
+
+cc2() {
+  try {
+    dd2();
+  } on SubclassOfError catch(e) {
+    rethrow;
+  } on int catch(e) {
+    fail();
+  }
+}
+
+dd2() => ee2();
+
+ee2() {
+  try {
+    ff2();
+  } catch(e) {
+    rethrow;
+  }
+}
+
+ff2() => gg2();
+
+gg2() => throw new SubclassOfError();
+
+// == Rethrow, with intervening catch without a trace parameter.
+
+aa3() {
+  try {
+    bb3();
+    fail();
+  } catch(error
+          , stacktrace  /// withtraceparameter: continued
+         ) {
+    expectTrace(['gg3', 'ff3', 'ee3', 'dd3', 'cc3', 'bb3', 'aa3'], error.stackTrace);
+    expectTrace(['cc3', 'bb3', 'aa3'], stacktrace);  /// withtraceparameter: continued
+  }
+}
+
+bb3() => cc3();
+
+cc3() {
+  try {
+    dd3();
+  } catch(e) {
+    throw e;
+  }
+}
+
+dd3() => ee3();
+
+ee3() {
+  try {
+    ff3();
+  } catch(e) {
+    rethrow;
+  }
+}
+
+ff3() => gg3();
+
+gg3() => throw new SubclassOfError();
+
+expectTrace(functionNames, stacktrace) {
+  // Note we don't expect functionNames to cover the whole trace, only the
+  // top portion, because the frames below main are an implementation detail.
+  var traceLines = stacktrace.toString().split('\n');
+  var expectedIndex = 0;
+  var actualIndex = 0;
+  print(stacktrace);
+  print(functionNames);
+  while (expectedIndex < functionNames.length) {
+    var expected = functionNames[expectedIndex];
+    var actual = traceLines[actualIndex];
+    if (actual.indexOf(expected) == -1) {
+      if (expectedIndex == 0) {
+        actualIndex++; // Skip over some helper frames at the top
+      } else {
+        throw "Expected: $expected actual: $actual";
+      }
+    } else {
+      actualIndex++;
+      expectedIndex++;
+    }
+  }
+}
+
+main() {
+  aa1();
+  aa2();
+  aa3();
+}