Ignore a11y failures in extension browser_tests that enter dev mode.

chrome/browser/ui/webui/extensions/extension_settings_browsertest.js

Index: chrome/browser/ui/webui/extensions/extension_settings_browsertest.js
diff --git a/chrome/browser/ui/webui/extensions/extension_settings_browsertest.js b/chrome/browser/ui/webui/extensions/extension_settings_browsertest.js
index 8183dc84cac804e3b2b14191ee045603b73a5346..ada780243ecd89d88c4f542a809a5163cce9bd13 100644
--- a/chrome/browser/ui/webui/extensions/extension_settings_browsertest.js
+++ b/chrome/browser/ui/webui/extensions/extension_settings_browsertest.js
@@ -88,6 +88,7 @@ ExtensionSettingsWebUITest.prototype = {
 
   /** @protected */
   verifyDeveloperModeWorks: function() {
+    this.ignoreDevModeA11yFailures();
     var extensionSettings = getRequiredElement('extension-settings');
     assertFalse(extensionSettings.classList.contains('dev-mode'));
     $('toggle-dev-on').click();
@@ -114,7 +115,25 @@ ExtensionSettingsWebUITest.prototype = {
                   this.verifyDeveloperModeWorks,
                   testDone];
     this.nextStep();
-  }
+  },
+
+  /**
+   * TODO(hcarmona): Remove this as part of fixing crbug.com/463245.
+   * Will ignore accessibility failures caused by the transition when developer
+   * mode is enabled.

[Devlin, 2015/04/27 15:49:24]

nit: I'd comment on why we ignore it, and why it's probably okay (and maybe do
the same briefly in the CL description).  (i.e., it fails because of an overlap,
but that overlap is only true during a short transition, so by the end it would
pass, if it could).

+   * @protected
+   */
+  ignoreDevModeA11yFailures: function() {
+    this.accessibilityAuditConfig.ignoreSelectors(
+          'focusableElementNotVisibleAndNotAriaHidden',
+          '#load-unpacked');
+    this.accessibilityAuditConfig.ignoreSelectors(
+          'focusableElementNotVisibleAndNotAriaHidden',
+          '#pack-extension');
+    this.accessibilityAuditConfig.ignoreSelectors(
+          'focusableElementNotVisibleAndNotAriaHidden',
+          '#update-extensions-now');
+  },
 };
 
 // Verify that developer mode doesn't change behavior when the number of