Fix for 593676 - Minimizes/eliminates momentary flash of Windows frame

ui/views/win/hwnd_message_handler.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 UI_VIEWS_WIN_HWND_MESSAGE_HANDLER_H_
 #define UI_VIEWS_WIN_HWND_MESSAGE_HANDLER_H_
 
 #include <windows.h>
 
 #include <stddef.h>
@@ skipping 193 matching lines @@
 
   // Updates the window style to reflect whether it can be resized or maximized.
   void SizeConstraintsChanged();
 
   // Returns true if content is rendered to a child window instead of directly
   // to this window.
   bool HasChildRenderingWindow();
 
  private:
   typedef std::set<DWORD> TouchIDs;
+  enum class DwmFrameState {OFF, ON};
 
   // Overridden from WindowImpl:
   HICON GetDefaultWindowIcon() const override;
   HICON GetSmallWindowIcon() const override;
   LRESULT OnWndProc(UINT message, WPARAM w_param, LPARAM l_param) override;
 
   // Overridden from WindowEventTarget
   LRESULT HandleMouseMessage(unsigned int message,
                              WPARAM w_param,
                              LPARAM l_param,
@@ skipping 83 matching lines @@
 
   // Stops ignoring SetWindowPos() requests (see below).
   void StopIgnoringPosChanges() { ignore_window_pos_changes_ = false; }
 
   // Attempts to force the window to be redrawn, ensuring that it gets
   // onscreen.
   void ForceRedrawWindow(int attempts);
 
   bool HasSystemFrame() const;
 
+  // Adds or removes the frame extension into client area with
+  // DwmExtendFrameIntoClientArea

[scottmg, 2016/06/29 22:35:37]

nit; . at end of sentence.

+  void SetDwmFrameExtension(DwmFrameState state);
+
   // Message Handlers ----------------------------------------------------------
 
   BEGIN_SAFE_MSG_MAP_EX(weak_factory_)
     // Range handlers must go first!
     CR_MESSAGE_RANGE_HANDLER_EX(WM_MOUSEFIRST, WM_MOUSELAST, OnMouseRange)
     CR_MESSAGE_RANGE_HANDLER_EX(WM_NCMOUSEMOVE,
                                 WM_NCXBUTTONDBLCLK,
                                 OnMouseRange)
 
     // CustomFrameWindow hacks
@@ skipping 348 matching lines @@
 
   // The factory used with BEGIN_SAFE_MSG_MAP_EX.
   base::WeakPtrFactory<HWNDMessageHandler> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(HWNDMessageHandler);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_WIN_HWND_MESSAGE_HANDLER_H_