GTK: Now that we depend on gtk 2.18+, replace this pattern:

chrome/browser/ui/gtk/bookmarks/bookmark_bar_gtk.cc

 // Copyright (c) 2011 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/gtk/bookmarks/bookmark_bar_gtk.h"
 
 #include <vector>
 
 #include "base/metrics/histogram.h"
 #include "base/utf_string_conversions.h"
@@ skipping 433 matching lines @@
         // The event box won't stay below its children's GdkWindows unless we
         // toggle the above-child property here. If the event box doesn't stay
         // below its children then events will be routed to it rather than the
         // children.
         gtk_event_box_set_above_child(GTK_EVENT_BOX(event_box_.get()), TRUE);
         gtk_event_box_set_above_child(GTK_EVENT_BOX(event_box_.get()), FALSE);
       }
     }
   }
 
-  if (sync_ui_util::ShouldShowSyncErrorButton(sync_service_)) {
-    gtk_widget_show(sync_error_button_);
-  } else {
-    gtk_widget_hide(sync_error_button_);
-  }
+  gtk_widget_set_visible(
+      sync_error_button_,
+      sync_ui_util::ShouldShowSyncErrorButton(sync_service_));
 
   // Maybe show the instructions
-  if (show_instructions_) {
-    gtk_widget_hide(bookmark_toolbar_.get());
-    gtk_widget_show(instructions_);
-  } else {
-    gtk_widget_hide(instructions_);
-    gtk_widget_show(bookmark_toolbar_.get());
-  }
+  gtk_widget_set_visible(bookmark_toolbar_.get(), !show_instructions_);
+  gtk_widget_set_visible(instructions_, show_instructions_);
 
   SetChevronState();
 }
 
 void BookmarkBarGtk::Hide(BookmarkBar::State old_state,
                           BookmarkBar::AnimateChangeType animate_type) {
   UpdateDetachedState(old_state);
 
   // After coming out of fullscreen, the browser window sets the bookmark bar
   // to the "hidden" state, which means we need to show our minimum height.
@@ skipping 24 matching lines @@
   }
 
   bookmark_utils::ConfigureButtonForNode(model_->other_node(),
       model_, other_bookmarks_button_, theme_service_);
 
   SetInstructionState();
   SetChevronState();
 }
 
 void BookmarkBarGtk::SetInstructionState() {
-  show_instructions_ = model_->GetBookmarkBarNode()->empty();
-  if (show_instructions_) {
-    gtk_widget_hide(bookmark_toolbar_.get());
-    gtk_widget_show_all(instructions_);
-  } else {
-    gtk_widget_hide(instructions_);
-    gtk_widget_show(bookmark_toolbar_.get());
-  }
+  if (model_)
+    show_instructions_ = model_->GetBookmarkBarNode()->empty();
+
+  gtk_widget_set_visible(bookmark_toolbar_.get(), !show_instructions_);
+  gtk_widget_set_visible(instructions_, show_instructions_);
 }
 
 void BookmarkBarGtk::SetChevronState() {
   if (!GTK_WIDGET_VISIBLE(bookmark_hbox_))
     return;
 
   if (show_instructions_) {
     gtk_widget_hide(overflow_button_);
     return;
   }
@@ skipping 893 matching lines @@
         method_factory_.NewRunnableMethod(
             &BookmarkBarGtk::PaintEventBox));
   }
 }
 
 void BookmarkBarGtk::OnThrobbingWidgetDestroy(GtkWidget* widget) {
   SetThrobbingWidget(NULL);
 }
 
 void BookmarkBarGtk::OnStateChanged() {
-  if (sync_ui_util::ShouldShowSyncErrorButton(sync_service_)) {
-    gtk_widget_show(sync_error_button_);
-  } else {
-    gtk_widget_hide(sync_error_button_);
-  }
+  gtk_widget_set_visible(
+      sync_error_button_,
+      sync_ui_util::ShouldShowSyncErrorButton(sync_service_));
 }
 
 void BookmarkBarGtk::ShowImportDialog() {
   browser_->OpenImportSettingsDialog();
 }
 
 void BookmarkBarGtk::OnEditBookmarksEnabledChanged() {
   GtkDestDefaults dest_defaults =
       *edit_bookmarks_enabled_ ? GTK_DEST_DEFAULT_ALL :
                                  GTK_DEST_DEFAULT_DROP;
   gtk_drag_dest_set(overflow_button_, dest_defaults, NULL, 0, kDragAction);
   gtk_drag_dest_set(other_bookmarks_button_, dest_defaults,
                     NULL, 0, kDragAction);
   ui::SetDestTargetList(overflow_button_, kDestTargetList);
   ui::SetDestTargetList(other_bookmarks_button_, kDestTargetList);
 }