Do not cancel request when an error occurs in a webRequest event handler

chrome/test/data/extensions/api_test/webrequest/test_api.js

Index: chrome/test/data/extensions/api_test/webrequest/test_api.js
diff --git a/chrome/test/data/extensions/api_test/webrequest/test_api.js b/chrome/test/data/extensions/api_test/webrequest/test_api.js
index b10a220714cb6d08163fb5b5dcd2b16bd4c9364f..399a7ca25d2b5154289a6b39867d0503fb179631 100644
--- a/chrome/test/data/extensions/api_test/webrequest/test_api.js
+++ b/chrome/test/data/extensions/api_test/webrequest/test_api.js
@@ -141,18 +141,19 @@ chrome.test.runTests([
       xhr.onload = function() {
         chrome.webRequest.onHeadersReceived.removeListener(
             callbackWithBadHeadersResponse);
-
-        chrome.test.fail();
-      };
-      xhr.onerror = function() {
-        chrome.webRequest.onHeadersReceived.removeListener(
-            callbackWithBadHeadersResponse);
-        // When the returned header is invalid, the request should be canceled.
+        var responseHeaders = xhr.getAllResponseHeaders() || '';
+        chrome.test.assertTrue(
+            responseHeaders.indexOf('X-Header-With-Invalid-Value') === -1);
         // TODO(robwu): If possible, check whether an error with the following
         // message has been logged to the JavaScript console:
         // "Header 'X-Header-With-Invalid-Value' has an invalid value"
         chrome.test.succeed();
       };
+      xhr.onerror = function() {
+        chrome.webRequest.onHeadersReceived.removeListener(
+            callbackWithBadHeadersResponse);
+        chrome.test.fail();
+      };
       xhr.send();
     });
   }