Fix Error.prototype.toString to throw TypeError.

test/mjsunit/regress/regress-1980.js

Index: test/mjsunit/regress/regress-1980.js
diff --git a/test/mjsunit/regress/regress-1980.js b/test/mjsunit/regress/regress-1980.js
new file mode 100644
index 0000000000000000000000000000000000000000..49dfd063bae26bd704b44024878d12ac28d62f1f
--- /dev/null
+++ b/test/mjsunit/regress/regress-1980.js
@@ -0,0 +1,40 @@
+// Copyright 2011 the V8 project authors. All rights reserved.
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+//       notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+//       copyright notice, this list of conditions and the following
+//       disclaimer in the documentation and/or other materials provided
+//       with the distribution.
+//     * Neither the name of Google Inc. nor the names of its
+//       contributors may be used to endorse or promote products derived
+//       from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// See: http://code.google.com/p/v8/issues/detail?id=1980
+
+var invalid_this = [ "invalid", 23, undefined, null ];
+for (var i = 0; i < invalid_this.length; i++) {
+  var exception = false;
+  try {
+    Error.prototype.toString.call(invalid_this[i]);
+  } catch (e) {
+    exception = true;
+    assertTrue("called_on_non_object" == e.type);
+  }
+  assertTrue(exception);
+}