Implement redirect() API for Fetch Response

LayoutTests/http/tests/fetch/script-tests/response.js

 if (self.importScripts) {
   importScripts('../resources/fetch-test-helpers.js');
 }
 
 function consume(reader) {
   var chunks = [];
   function rec(reader) {
     return reader.read().then(function(r) {
         if (r.done) {
           return chunks;
@@ skipping 99 matching lines @@
                   'Response.headers must not have Content-Type ' +
                   'for Blob with type = empty string (2)');
   }, 'Response content type test');
 
 test(function() {
     [0, 1, 100, 199, 600, 700].forEach(function(status) {
         assert_throws({name: 'RangeError'},
                       function() {
                         new Response(new Blob(), {status: status});
                       },
-                      'new Response with status = ' + status + ' should throw');
+                      'new Response with status = ' + status +
+                      'should throw');
       });
+
+    [300, 0, 304, 305, 306, 309, 500].forEach(function(status) {
+        assert_throws({name: 'RangeError'},
+                      function() {
+                        Response.redirect('https://www.example.com/test.html',
+                                          status);
+                      },
+                      'Response.redirect() with invalid status = ' + status +
+                      'should throw');
+      });
+
+    assert_throws(
+      {name: 'TypeError'},
+      function() {
+        Response.redirect('https://', 301);
+      },
+      'Response.redirect() with invalid URL https://' +
+      'status as 301 should throw');

[hiroshige, 2015/04/27 11:47:25]

nit: ' and status 301 should throw'.
- space after https://
- inserting "and"

[shiva.jm, 2015/04/28 06:06:48]

Done.

+
+    INVALID_URLS.forEach(function(url) {
+        assert_throws(
+          {name: 'TypeError'},
+          function() {
+            Response.redirect(url);
+          },
+          'Response.redirect() with invalid URL' + url +

[hiroshige, 2015/04/27 11:47:25]

nit: 'Response.redirect() with invalid URL ' + url +
' and default status value should throw'.
- spaces before/after url
- inserting "and"

[shiva.jm, 2015/04/28 06:06:48]

Done.

+          'default status value should throw');
+      });
+
+    assert_throws(
+      {name: 'TypeError'},
+      function() {
+        Response.redirect('https://', 300);
+      },
+      'Response.redirect() with invalid URL https://' +
+      'invalid status 300 should throw');

[hiroshige, 2015/04/27 11:47:25]

nit: ' and invalid status 300 should throw TypeError'
- spaces before/after url
- inserting "and"
- inserting "TypeError" (because this shouldn't throw RangeError)

[shiva.jm, 2015/04/28 06:06:48]

Done.

+
     [200, 300, 400, 500, 599].forEach(function(status) {
         var response = new Response(new Blob(), {status: status});
         assert_equals(response.status, status, 'Response.status should match');
         if (200 <= status && status <= 299)
           assert_true(response.ok, 'Response.ok must be true for ' + status);
         else
           assert_false(response.ok, 'Response.ok must be false for ' + status);
       });
 
     INVALID_HEADER_NAMES.forEach(function(name) {
@@ skipping 286 matching lines @@
       }).then(function(texts) {
         assert_equals(texts[0], '');
         assert_equals(texts[1], '');
         return res.body.getReader().read();
       }).then(function(r) {
         assert_true(r.done);
         assert_equals(r.value, undefined);
       });
   }, 'Read after text()');
 
+promise_test(function() {
+    var response = Response.redirect('https://www.example.com/test.html');
+    return response.text().then(function(text) {
+        assert_equals(response.status, 302,
+                      'default value of status is always 302');
+        assert_equals(response.headers.get('location'),
+                      'https://www.example.com/test.html',
+                      'Location header should be correct absoulte URL');
+        assert_throws({name: 'TypeError'},
+                      function() {
+                        response.headers.append('Accept-Language', 'test');
+                      },
+                      'response.headers must throw since guard is immutable');
+      });
+  }, 'Response.redirect() with default status value');
+
+promise_test(function() {
+    var response = Response.redirect('https://www.example.com/test.html',
+                                     301);
+    return response.text().then(function(text) {
+        assert_equals(response.status, 301,
+                      'value of status is 301');
+        assert_equals(response.headers.get('location'),
+                      'https://www.example.com/test.html',
+                      'Location header should be correct absoulte URL');
+      });
+  }, 'Response.redirect() with 301');
+
 done();