Proper rendering of stacked tabs for MD.

chrome/browser/ui/views/tabs/tab.h

 // 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.
 
 #ifndef CHROME_BROWSER_UI_VIEWS_TABS_TAB_H_
 #define CHROME_BROWSER_UI_VIEWS_TABS_TAB_H_
 
 #include <list>
 #include <memory>
 #include <string>
@@ skipping 213 matching lines @@
   // ui::EventHandler:
   void OnGestureEvent(ui::GestureEvent* event) override;
 
   // Invoked from Layout to adjust the position of the favicon or alert
   // indicator for pinned tabs.
   void MaybeAdjustLeftForPinnedTab(gfx::Rect* bounds) const;
 
   // Invoked from SetData after |data_| has been updated to the new data.
   void DataChanged(const TabRendererData& old);
 
-  // Paint with the normal tab style.
-  void PaintTab(gfx::Canvas* canvas);
+  // Paint with the normal tab style.  If |clip| is non-empty, the tab border
+  // should be clipped against it.
+  void PaintTab(gfx::Canvas* canvas, const gfx::Path& clip);
 
   // Paint with the "immersive mode" light-bar style.
   void PaintImmersiveTab(gfx::Canvas* canvas);
 
   // Paint various portions of the Tab.
-  void PaintInactiveTabBackground(gfx::Canvas* canvas);
-  void PaintTabBackgroundUsingFillId(gfx::Canvas* canvas,
+  void PaintInactiveTabBackground(gfx::Canvas* canvas, const gfx::Path& clip);
+  void PaintTabBackgroundUsingFillId(gfx::Canvas* fill_canvas,
+                                     gfx::Canvas* stroke_canvas,
                                      bool is_active,
                                      int fill_id,
                                      bool has_custom_image,
                                      int y_offset);
 
   // Paints the pinned tab title changed indicator and |favicon_|. |favicon_|
   // may be null. |favicon_draw_bounds| is |favicon_bounds_| adjusted for rtl
   // and clipped to the bounds of the tab.
   void PaintPinnedTabTitleChangedIndicatorAndIcon(
       gfx::Canvas* canvas,
@@ skipping 109 matching lines @@
 
   // The favicon for the tab. This might be the sad tab icon or a copy of
   // data().favicon and may be modified for theming. It is created on demand
   // and thus may be null.
   gfx::ImageSkia favicon_;
 
   DISALLOW_COPY_AND_ASSIGN(Tab);
 };
 
 #endif  // CHROME_BROWSER_UI_VIEWS_TABS_TAB_H_