Add initial GTK web accessibility framework.

content/browser/accessibility/browser_accessibility_manager_gtk.cc

+// Copyright (c) 2012 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.
+
+#include "content/browser/accessibility/browser_accessibility_manager_gtk.h"
+
+#include "content/browser/accessibility/browser_accessibility_gtk.h"
+#include "content/common/accessibility_messages.h"
+
+using webkit_glue::WebAccessibility;
+
+// static
+BrowserAccessibilityManager* BrowserAccessibilityManager::Create(
+    gfx::NativeView parent_view,
+    const WebAccessibility& src,
+    BrowserAccessibilityDelegate* delegate,
+    BrowserAccessibilityFactory* factory) {
+  return new BrowserAccessibilityManagerGtk(
+      parent_view,
+      src,
+      delegate,
+      factory);
+}
+
+BrowserAccessibilityManagerGtk::BrowserAccessibilityManagerGtk(
+    GtkWidget* parent_view,
+    const WebAccessibility& src,
+    BrowserAccessibilityDelegate* delegate,
+    BrowserAccessibilityFactory* factory)
+    : BrowserAccessibilityManager(parent_view, src, delegate, factory) {
+}
+
+BrowserAccessibilityManagerGtk::~BrowserAccessibilityManagerGtk() {
+}
+
+void BrowserAccessibilityManagerGtk::NotifyAccessibilityEvent(
+    int type,
+    BrowserAccessibility* node) {
+  AtkObject* atk_object = node->ToBrowserAccessibilityGtk()->GetAtkObject();
+
+  switch (type) {

[David Tseng, 2012/05/02 18:02:58]

Might have to switch on all enum values (somewhat remember it being a clang
warning -> error on one of the bots). Run it through the try bots to see.

[dmazzoni, 2012/05/02 19:33:05]

It's okay as long as there's a default in the switch. Often it's better to not
have a default so that you get a compiler error if you miss an enum, but for now
this is probably better since we've hardly implemented any of them.

+    case AccessibilityNotificationChildrenChanged:
+      RecursivelySendChildrenChanged(GetRoot()->ToBrowserAccessibilityGtk());
+      break;
+    case AccessibilityNotificationFocusChanged:
+      g_signal_emit_by_name(atk_object, "focus-event", true);

[David Tseng, 2012/05/02 18:02:58]

Add a note here to pick the authoritative way of sending focus events (state
changed, focus event, or focus tracker notify) once the alternatives actually
work (reference 
https://bugzilla.gnome.org/show_bug.cgi?id=649575#c4
)

[dmazzoni, 2012/05/02 19:33:05]

Done.

+      atk_focus_tracker_notify(atk_object);
+      break;
+    default:
+      break;
+  }
+}
+
+void BrowserAccessibilityManagerGtk::RecursivelySendChildrenChanged(
+    BrowserAccessibilityGtk* node) {
+  AtkObject* atkObject = node->ToBrowserAccessibilityGtk()->GetAtkObject();
+  for (unsigned int i = 0; i < node->children().size(); ++i) {
+    BrowserAccessibilityGtk* child =
+        node->children()[i]->ToBrowserAccessibilityGtk();
+    g_signal_emit_by_name(atkObject,
+                          "children-changed::add",
+                          i,
+                          child->GetAtkObject());
+    RecursivelySendChildrenChanged(child);
+  }
+}