Custom frame UI for platform apps on Windows.

content/browser/renderer_host/render_widget_host_view_win.h

Index: content/browser/renderer_host/render_widget_host_view_win.h
diff --git a/content/browser/renderer_host/render_widget_host_view_win.h b/content/browser/renderer_host/render_widget_host_view_win.h
index b5c09304f5115d553db9e49f623df97a64b837fa..5fac29cc8d5faa3f126cdddd5dd8a001f4383748 100644
--- a/content/browser/renderer_host/render_widget_host_view_win.h
+++ b/content/browser/renderer_host/render_widget_host_view_win.h
@@ -27,6 +27,7 @@
 #include "ui/base/win/ime_input.h"
 #include "ui/gfx/native_widget_types.h"
 #include "ui/gfx/point.h"
+#include "ui/gfx/scoped_sk_region.h"
 #include "ui/gfx/surface/accelerated_surface_win.h"
 #include "webkit/glue/webcursor.h"
 
@@ -107,6 +108,7 @@ class RenderWidgetHostViewWin
     MSG_WM_DESTROY(OnDestroy)
     MSG_WM_PAINT(OnPaint)
     MSG_WM_NCPAINT(OnNCPaint)
+    MSG_WM_NCHITTEST(OnNCHitTest)
     MSG_WM_ERASEBKGND(OnEraseBkgnd)
     MSG_WM_SETCURSOR(OnSetCursor)
     MSG_WM_SETFOCUS(OnSetFocus)
@@ -225,6 +227,8 @@ class RenderWidgetHostViewWin
   virtual void AccessibilitySetTextSelection(
       int acc_obj_id, int start_offset, int end_offset) OVERRIDE;
 
+  virtual void SetTransparentRegion(SkRegion* region);
+
  protected:
   // Windows Message Handlers
   LRESULT OnCreate(CREATESTRUCT* create_struct);
@@ -232,6 +236,7 @@ class RenderWidgetHostViewWin
   void OnDestroy();
   void OnPaint(HDC unused_dc);
   void OnNCPaint(HRGN update_region);
+  LRESULT OnNCHitTest(const CPoint& pt);
   LRESULT OnEraseBkgnd(HDC dc);
   LRESULT OnSetCursor(HWND window, UINT hittest_code, UINT mouse_message_id);
   void OnSetFocus(HWND window);
@@ -537,6 +542,9 @@ class RenderWidgetHostViewWin
   // Set to true if we received a focus change after a WM_POINTERDOWN message.
   bool received_focus_change_after_pointer_down_;
 
+  // Region in which the view will be transparent to clicks.
+  gfx::ScopedSkRegion transparent_region_;
+
   DISALLOW_COPY_AND_ASSIGN(RenderWidgetHostViewWin);
 };