Fix regression of webview loadstart events firing for same page navigations.

extensions/test/data/web_view/apitest/main.js

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 var embedder = {};
 
 // TODO(lfg) Move these functions to a common js.
 embedder.setUp_ = function(config) {
   if (!config || !config.testServer) {
     return;
   }
   embedder.baseGuestURL = 'http://localhost:' + config.testServer.port;
   embedder.closeSocketURL = embedder.baseGuestURL + '/close-socket';
   embedder.emptyGuestURL = embedder.baseGuestURL + '/empty_guest.html';
   embedder.noReferrerGuestURL =
       embedder.baseGuestURL + '/guest_noreferrer.html';
   embedder.detectUserAgentURL = embedder.baseGuestURL + '/detect-user-agent';
   embedder.redirectGuestURL = embedder.baseGuestURL + '/server-redirect';
   embedder.redirectGuestURLDest =
       embedder.baseGuestURL + '/guest_redirect.html';
   embedder.windowOpenGuestURL = embedder.baseGuestURL + '/guest.html';
+  embedder.samePageNavigationURL =
+      embedder.baseGuestURL + '/guest_same_page_navigation.html';
 };
 
 window.runTest = function(testName) {
   if (!embedder.test.testList[testName]) {
     window.console.warn('Incorrect testName: ' + testName);
     embedder.test.fail();
     return;
   }
 
   // Run the test.
@@ skipping 1011 matching lines @@
     embedder.test.succeed();
   });
   webview.addEventListener('exit', function(e) {
     // We should not crash.
     embedder.test.fail();
   });
   webview.src = chromeGuestURL;
   document.body.appendChild(webview);
 };
 
+// This test verifies that the loadStart isn't sent for same page navigations,
+// while loadCommit is (per docs).
+function testLoadEventsSamePageNavigation() {
+  var webview = new WebView();
+  var loadStartCount = 0;
+  var loadCommitCount = 0;
+  webview.addEventListener('loadstart', function(evt) {
+    loadStartCount++;
+  });
+  webview.addEventListener('loadcommit', function(e) {
+    loadCommitCount++;
+  });
+  webview.addEventListener('loadstop', function(evt) {
+    embedder.test.assertEq(1, loadStartCount);
+    embedder.test.assertEq(2, loadCommitCount);
+    embedder.test.succeed();
+  });
+
+  webview.src = embedder.samePageNavigationURL;
+  document.body.appendChild(webview);
+}
+
 // Tests that the 'loadprogress' event is triggered correctly.
 function testLoadProgressEvent() {
   var webview = document.createElement('webview');
   var progress = 0;
 
   webview.addEventListener('loadstop', function(evt) {
     embedder.test.assertEq(1, progress);
     embedder.test.succeed();
   });
 
@@ skipping 686 matching lines @@
       testInlineScriptFromAccessibleResources,
   'testInvalidChromeExtensionURL': testInvalidChromeExtensionURL,
   'testLoadAbortChromeExtensionURLWrongPartition':
       testLoadAbortChromeExtensionURLWrongPartition,
   'testLoadAbortEmptyResponse': testLoadAbortEmptyResponse,
   'testLoadAbortIllegalChromeURL': testLoadAbortIllegalChromeURL,
   'testLoadAbortIllegalFileURL': testLoadAbortIllegalFileURL,
   'testLoadAbortIllegalJavaScriptURL': testLoadAbortIllegalJavaScriptURL,
   'testLoadAbortInvalidNavigation': testLoadAbortInvalidNavigation,
   'testLoadAbortNonWebSafeScheme': testLoadAbortNonWebSafeScheme,
+  'testLoadEventsSamePageNavigation': testLoadEventsSamePageNavigation,
   'testLoadProgressEvent': testLoadProgressEvent,
   'testLoadStartLoadRedirect': testLoadStartLoadRedirect,
   'testNavigateAfterResize': testNavigateAfterResize,
   'testNavigationToExternalProtocol': testNavigationToExternalProtocol,
   'testNavOnConsecutiveSrcAttributeChanges':
       testNavOnConsecutiveSrcAttributeChanges,
   'testNavOnSrcAttributeChange': testNavOnSrcAttributeChange,
   'testNewWindow': testNewWindow,
   'testNewWindowNoPreventDefault': testNewWindowNoPreventDefault,
   'testNewWindowNoReferrerLink': testNewWindowNoReferrerLink,
@@ skipping 16 matching lines @@
   'testWebRequestAPIGoogleProperty': testWebRequestAPIGoogleProperty,
   'testCaptureVisibleRegion': testCaptureVisibleRegion
 };
 
 onload = function() {
   chrome.test.getConfig(function(config) {
     embedder.setUp_(config);
     chrome.test.sendMessage('LAUNCHED');
   });
 };