MacViews: Implement Full Keyboard Access.

ui/views/cocoa/bridged_native_widget.mm

Index: ui/views/cocoa/bridged_native_widget.mm
diff --git a/ui/views/cocoa/bridged_native_widget.mm b/ui/views/cocoa/bridged_native_widget.mm
index 6f5dec0f96864ede56c8a7cf940de5ebf964aa92..3bb293b47cf0aa8c7f3ae373814f56260d6dc4cc 100644
--- a/ui/views/cocoa/bridged_native_widget.mm
+++ b/ui/views/cocoa/bridged_native_widget.mm
@@ -351,6 +351,14 @@ void BridgedNativeWidget::Init(base::scoped_nsobject<NSWindow> window,
              name:NSApplicationDidHideNotification
            object:nil];
 
+  // Get notified whenever Full Keyboard Access mode is changed.
+  // Todo(karandeepb): See how to store constant string.

[tapted, 2016/02/23 03:01:19]

You can just declare a

NSString* const kFullKeyboardAccessChangedNotification =
    @"com.apple.KeyboardUIModeDidChange";

in an anonymous namespace

[karandeepb, 2016/03/15 02:19:50]

Done.

+  [[NSDistributedNotificationCenter defaultCenter]
+      addObserver:window_delegate_
+         selector:@selector(onFullKeyboardAccessModeChanged:)
+             name:@"com.apple.KeyboardUIModeDidChange"
+           object:nil];
+
   // Validate the window's initial state, otherwise the bridge's initial
   // tracking state will be incorrect.
   DCHECK(![window_ isVisible]);
@@ -426,8 +434,11 @@ void BridgedNativeWidget::SetFocusManager(FocusManager* focus_manager) {
   if (focus_manager_)
     focus_manager_->RemoveFocusChangeListener(this);
 
-  if (focus_manager)
+  if (focus_manager) {
     focus_manager->AddFocusChangeListener(this);
+    focus_manager->SetKeyboardAccessibility(
+        [NSApp isFullKeyboardAccessEnabled]);
+  }
 
   focus_manager_ = focus_manager;
 }
@@ -596,6 +607,8 @@ void BridgedNativeWidget::OnWindowWillClose() {
   }
   [window_ setDelegate:nil];
   [[NSNotificationCenter defaultCenter] removeObserver:window_delegate_];
+  [[NSDistributedNotificationCenter defaultCenter]
+      removeObserver:window_delegate_];
   native_widget_mac_->OnWindowWillClose();
 }
 
@@ -758,6 +771,14 @@ void BridgedNativeWidget::OnWindowKeyStatusChangedTo(bool is_key) {
   if ([window_ contentView] == [window_ firstResponder]) {
     if (is_key) {
       widget->OnNativeFocus();
+      // The NSApplication class automatically suspends distributed notification
+      // delivery when the application is not active. For the full keyboard
+      // access mode change notification, the default suspension behavior of
+      // NSNotificationSuspensionBehaviorCoalesce should have worked, but
+      // it doesn't sometimes. Hence explicitly set the keyboard accessibility
+      // state on regaining key window status.
+      widget->GetFocusManager()->SetKeyboardAccessibility(
+          [NSApp isFullKeyboardAccessEnabled]);
       widget->GetFocusManager()->RestoreFocusedView();
     } else {
       widget->OnNativeBlur();