Merge to M51: Don't send focus accessibility events when tab isn't focused.

content/browser/accessibility/browser_accessibility_manager.cc

Index: content/browser/accessibility/browser_accessibility_manager.cc
diff --git a/content/browser/accessibility/browser_accessibility_manager.cc b/content/browser/accessibility/browser_accessibility_manager.cc
index 44d1d408e68f36bde58ef134f25e7a913b810f91..f95f5085c3316058b3818b7fc08717eeea1e12fe 100644
--- a/content/browser/accessibility/browser_accessibility_manager.cc
+++ b/content/browser/accessibility/browser_accessibility_manager.cc
@@ -188,7 +188,7 @@ void BrowserAccessibilityManager::FireFocusEventsIfNeeded() {
   // Don't fire focus events if the window itself doesn't have focus.
   // Bypass this check if a global focus listener was set up for testing
   // so that the test passes whether the window is active or not.
-  if (!g_focus_change_callback_for_testing.Pointer()) {
+  if (g_focus_change_callback_for_testing.Get().is_null()) {
     if (delegate_ && !delegate_->AccessibilityViewHasFocus())
       focus = nullptr;