MacViews: Implement Full Keyboard Access.

ui/views/controls/webview/webview.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 "ui/views/controls/webview/webview.h"
 
 #include <utility>
 
 #include "build/build_config.h"
 #include "content/public/browser/browser_accessibility_state.h"
@@ skipping 49 matching lines @@
   WebContentsObserver::Observe(replacement);
   if (observing_render_process_host_) {
     observing_render_process_host_->RemoveObserver(this);
     observing_render_process_host_ = nullptr;
   }
   if (web_contents() && web_contents()->GetRenderProcessHost()) {
     observing_render_process_host_ = web_contents()->GetRenderProcessHost();
     observing_render_process_host_->AddObserver(this);
   }
   // web_contents() now returns |replacement| from here onwards.
-  SetFocusable(!!web_contents());
+  SetFocusBehavior(web_contents() ? FocusBehavior::CONTROL
+                                  : FocusBehavior::NEVER);
   if (wc_owner_.get() != replacement)
     wc_owner_.reset();
   if (embed_fullscreen_widget_mode_enabled_) {
     is_embedding_fullscreen_widget_ =
         web_contents() && web_contents()->GetFullscreenRenderWidgetHostView();
   } else {
     DCHECK(!is_embedding_fullscreen_widget_);
   }
   AttachWebContents();
   NotifyAccessibilityWebContentsChanged();
@@ skipping 313 matching lines @@
   if (!contents) {
     content::WebContents::CreateParams create_params(
         browser_context, NULL);
     return content::WebContents::Create(create_params);
   }
 
   return contents;
 }
 
 }  // namespace views