Adds clipping to the tabs when stacked. This is necessary so we don't

chrome/browser/ui/views/tabs/tab.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 "chrome/browser/ui/views/tabs/tab.h"
 
 #include <limits>
 
 #include "base/utf_string_conversions.h"
 #include "chrome/browser/defaults.h"
@@ skipping 284 matching lines @@
 
 ////////////////////////////////////////////////////////////////////////////////
 // Tab, views::View overrides:
 
 void Tab::OnPaint(gfx::Canvas* canvas) {
   // Don't paint if we're narrower than we can render correctly. (This should
   // only happen during animations).
   if (width() < GetMinimumUnselectedSize().width() && !data().mini)
     return;
 
+  gfx::Rect clip;
+  if (controller()) {
+    if (!controller()->ShouldPaintTab(this, &clip))
+      return;
+    if (!clip.IsEmpty()) {
+      canvas->Save();
+      canvas->ClipRect(clip);
+    }
+  }
+
   // See if the model changes whether the icons should be painted.
   const bool show_icon = ShouldShowIcon();
   const bool show_close_button = ShouldShowCloseBox();
   if (show_icon != showing_icon_ || show_close_button != showing_close_button_)
     Layout();
 
   PaintTabBackground(canvas);
 
   SkColor title_color = GetThemeProvider()->
       GetColor(IsSelected() ?
           ThemeService::COLOR_TAB_TEXT :
           ThemeService::COLOR_BACKGROUND_TAB_TEXT);
 
   if (!data().mini || width() > kMiniTabRendererAsNormalTabWidth)
     PaintTitle(canvas, title_color);
 
   if (show_icon)
     PaintIcon(canvas);
 
   // If the close button color has changed, generate a new one.
   if (!close_button_color_ || title_color != close_button_color_) {
     close_button_color_ = title_color;
     ui::ResourceBundle& rb = ui::ResourceBundle::GetSharedInstance();
     close_button()->SetBackground(close_button_color_,
         rb.GetImageSkiaNamed(IDR_TAB_CLOSE),
         rb.GetImageSkiaNamed(IDR_TAB_CLOSE_MASK));
   }
+
+  if (!clip.IsEmpty())
+    canvas->Restore();
 }
 
 void Tab::Layout() {
   gfx::Rect lb = GetContentsBounds();
   if (lb.IsEmpty())
     return;
   lb.Inset(
       left_padding(), top_padding(), right_padding(), bottom_padding());
 
   // The height of the content of the Tab is the largest of the favicon,
@@ skipping 372 matching lines @@
   tab_active_.image_r = rb.GetBitmapNamed(IDR_TAB_ACTIVE_RIGHT);
   tab_active_.l_width = tab_active_.image_l->width();
   tab_active_.r_width = tab_active_.image_r->width();
 
   tab_inactive_.image_l = rb.GetBitmapNamed(IDR_TAB_INACTIVE_LEFT);
   tab_inactive_.image_c = rb.GetBitmapNamed(IDR_TAB_INACTIVE_CENTER);
   tab_inactive_.image_r = rb.GetBitmapNamed(IDR_TAB_INACTIVE_RIGHT);
   tab_inactive_.l_width = tab_inactive_.image_l->width();
   tab_inactive_.r_width = tab_inactive_.image_r->width();
 }