Implement URLSearchParams.

LayoutTests/fast/domurl/url-constructor.html

Index: LayoutTests/fast/domurl/url-constructor.html
diff --git a/LayoutTests/fast/domurl/url-constructor.html b/LayoutTests/fast/domurl/url-constructor.html
index 1091b3e7c960adf8f1fc5eb0aff384d0e121130c..2409940cfa342d5ecb5c6bc752fc08dd486604d1 100644
--- a/LayoutTests/fast/domurl/url-constructor.html
+++ b/LayoutTests/fast/domurl/url-constructor.html
@@ -2,18 +2,8 @@
 <link rel="help" href="http://url.spec.whatwg.org/#dom-url">
 <script src="../../resources/testharness.js"></script>
 <script src="../../resources/testharnessreport.js"></script>
+<script src="resources/testharness-extras.js"></script>
 <script>
-
-function assertThrows(func, expected) {
-    try {
-        func();
-    } catch (ex) {
-        assert_equals(String(ex), expected);
-        return;
-    }
-    assert_true(false, 'Expected an exception with string: ' + expected);
-}
-
 test(function() {
     assert_equals(new URL('http://www.domain.com/a/b').toString(), 'http://www.domain.com/a/b');
     assert_equals(new URL('/c/d', 'http://www.domain.com/a/b').toString(), 'http://www.domain.com/c/d');
@@ -28,21 +18,16 @@ test(function() {
 }, 'Valid URLs');
 
 test(function() {
-    assertThrows(function() {
-        new URL();
-    }, 'TypeError: Failed to construct \'URL\': 1 argument required, but only 0 present.');
-    assertThrows(function() {
-        new URL('abc');
-    }, 'SyntaxError: Failed to construct \'URL\': Invalid URL');
-    assertThrows(function() {
-        new URL('//abc');
-    }, 'SyntaxError: Failed to construct \'URL\': Invalid URL');
-    assertThrows(function() {
-        new URL('http:///www.domain.com/', 'abc');
-    }, 'SyntaxError: Failed to construct \'URL\': Invalid base URL');
-    assertThrows(function() {
-        new URL('http:///www.domain.com/', null);
-    }, 'SyntaxError: Failed to construct \'URL\': Invalid base URL');
+    assert_throws_message(function() {new URL();},
+        'TypeError: Failed to construct \'URL\': 1 argument required, but only 0 present.', 'TypeError');
+    assert_throws_message(function() { new URL('abc'); },
+        'SyntaxError: Failed to construct \'URL\': Invalid URL');
+    assert_throws_message(function() { new URL('//abc'); },
+        'SyntaxError: Failed to construct \'URL\': Invalid URL');
+    assert_throws_message(function() { new URL('http:///www.domain.com/', 'abc'); },
+        'SyntaxError: Failed to construct \'URL\': Invalid base URL');
+    assert_throws_message(function() { new URL('http:///www.domain.com/', null); },
+         'SyntaxError: Failed to construct \'URL\': Invalid base URL');
 }, 'Invalid URL parameters');
 
 </script>