Allow keyboard shortcuts can be captured by webpage when toolbar is not visible

chrome/browser/ui/cocoa/browser_window_cocoa.mm

 // 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 "chrome/browser/ui/cocoa/browser_window_cocoa.h"
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/logging.h"
 #import "base/mac/sdk_forward_declarations.h"
@@ skipping 304 matching lines @@
   } else if (alert_state_ == TabAlertState::AUDIO_MUTING) {
     return l10n_util::GetNSStringF(IDS_WINDOW_AUDIO_MUTING_MAC,
                                    browser_->GetWindowTitleForCurrentTab(
                                        include_app_name),
                                    base::SysNSStringToUTF16(@"🔇"));
   }
   return base::SysUTF16ToNSString(
       browser_->GetWindowTitleForCurrentTab(include_app_name));
 }
 
+bool BrowserWindowCocoa::IsToolbarShowing() const {
+  if (!IsFullscreen()) {
+    return true;
+  }
+
+  // TODO(zijiehe): Retrieve the visibility of toolbar from

[msw, 2017/04/04 19:32:48]

Is this okay to leave as a TODO? It seems like that's why this was reverted
previously? Please seek reviewers for this aspect of the change before seeking
owners review.

[Hzj_jie, 2017/04/04 20:54:43]

As long as this function returns true, the behavior should keep unchanged.
I have not received my Mac workstation yet. So unfortunately I cannot implement
it blindly now.

+  // FullscreenToolbarController.
+  return true;
+}
+
 void BrowserWindowCocoa::BookmarkBarStateChanged(
     BookmarkBar::AnimateChangeType change_type) {
   [[controller_ bookmarkBarController]
       updateState:browser_->bookmark_bar_state()
        changeType:change_type];
 }
 
 void BrowserWindowCocoa::UpdateDevTools() {
   [controller_ updateDevToolsForContents:
       browser_->tab_strip_model()->GetActiveWebContents()];
@@ skipping 505 matching lines @@
 ExclusiveAccessContext* BrowserWindowCocoa::GetExclusiveAccessContext() {
   return [controller_ exclusiveAccessController];
 }
 
 void BrowserWindowCocoa::ShowImeWarningBubble(
     const extensions::Extension* extension,
     const base::Callback<void(ImeWarningBubblePermissionStatus status)>&
         callback) {
   NOTREACHED() << "The IME warning bubble is unsupported on this platform.";
 }