Revert "Fix a ton of compiler warnings."

chrome/browser/gtk/tabs/tab_renderer_gtk.cc

 // Copyright (c) 2009 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/gtk/tabs/tab_renderer_gtk.h"
 
 #include <algorithm>
 #include <utility>
 
 #include "app/gfx/canvas_paint.h"
@@ skipping 218 matching lines @@
 
 ////////////////////////////////////////////////////////////////////////////////
 // TabRendererGtk, public:
 
 TabRendererGtk::TabRendererGtk(ThemeProvider* theme_provider)
     : showing_icon_(false),
       showing_close_button_(false),
       fav_icon_hiding_offset_(0),
       should_display_crashed_favicon_(false),
       loading_animation_(theme_provider),
-      // Zero is not a valid SkColor.  It'll be replaced by the
-      // theme tab_text_color.
-      close_button_color_(0u) {
+      close_button_color_(NULL) {
   InitResources();
 
   data_.pinned = false;
 
   tab_.Own(gtk_fixed_new());
   gtk_widget_set_app_paintable(tab_.get(), TRUE);
   g_signal_connect(G_OBJECT(tab_.get()), "expose-event",
                    G_CALLBACK(OnExposeEvent), this);
   g_signal_connect(G_OBJECT(tab_.get()), "size-allocate",
                    G_CALLBACK(OnSizeAllocate), this);
@@ skipping 333 matching lines @@
         kTopPadding + kCloseButtonVertFuzz +
         (content_height - close_button_height_) / 2;
     close_button_bounds_.SetRect(local_bounds.width() + kCloseButtonHorzFuzz,
                                  close_button_top, close_button_width_,
                                  close_button_height_);
 
     // If the close button color has changed, generate a new one.
     if (theme_provider_) {
       SkColor tab_text_color =
         theme_provider_->GetColor(BrowserThemeProvider::COLOR_TAB_TEXT);
-      if (close_button_color_ == 0u || tab_text_color != close_button_color_) {
+      if (!close_button_color_ || tab_text_color != close_button_color_) {
         close_button_color_ = tab_text_color;
         ResourceBundle& rb = ResourceBundle::GetSharedInstance();
         close_button_->SetBackground(close_button_color_,
             rb.GetBitmapNamed(IDR_TAB_CLOSE),
             rb.GetBitmapNamed(IDR_TAB_CLOSE_MASK));
       }
     }
   } else {
     close_button_bounds_.SetRect(0, 0, 0, 0);
   }
@@ skipping 383 matching lines @@
   // Force the font size to 9pt, which matches Windows' default font size
   // (taken from the system).
   gfx::Font base_font = rb.GetFont(ResourceBundle::BaseFont);
   title_font_ = new gfx::Font(gfx::Font::CreateFont(base_font.FontName(), 9));
   title_font_height_ = title_font_->height();
 
   crashed_fav_icon = rb.GetBitmapNamed(IDR_SAD_FAVICON);
 
   initialized_ = true;
 }