Fix a long standing painting problem seen in the tabstrip on Windows Desktop Chrome.

ui/views/win/hwnd_message_handler.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 "ui/views/win/hwnd_message_handler.h"
 
 #include <dwmapi.h>
 #include <oleacc.h>
 #include <shellapi.h>
 #include <wtsapi32.h>
@@ skipping 341 matching lines @@
       layered_alpha_(255),
       waiting_for_redraw_layered_window_contents_(false),
       is_first_nccalc_(true),
       menu_depth_(0),
       autohide_factory_(this),
       id_generator_(0),
       needs_scroll_styles_(false),
       in_size_loop_(false),
       touch_down_contexts_(0),
       last_mouse_hwheel_time_(0),
-      msg_handled_(FALSE) {
+      msg_handled_(FALSE),
+      dwm_transition_desired_(false) {
 }
 
 HWNDMessageHandler::~HWNDMessageHandler() {
   delegate_ = NULL;
   // Prevent calls back into this class via WNDPROC now that we've been
   // destroyed.
   ClearUserData();
 }
 
 void HWNDMessageHandler::Init(HWND parent, const gfx::Rect& bounds) {
@@ skipping 414 matching lines @@
   if (cursor) {
     previous_cursor_ = ::SetCursor(cursor);
     current_cursor_ = cursor;
   } else if (previous_cursor_) {
     ::SetCursor(previous_cursor_);
     previous_cursor_ = NULL;
   }
 }
 
 void HWNDMessageHandler::FrameTypeChanged() {
-  // Called when the frame type could possibly be changing (theme change or
-  // DWM composition change).
-  UpdateDwmNcRenderingPolicy();
-
-  // Don't redraw the window here, because we need to hide and show the window
-  // which will also trigger a redraw.
-  ResetWindowRegion(true, false);
-
-  // The non-client view needs to update too.
-  delegate_->HandleFrameChanged();
-
-  if (IsVisible() && !delegate_->IsUsingCustomFrame()) {
-    // For some reason, we need to hide the window after we change from a custom
-    // frame to a native frame.  If we don't, the client area will be filled
-    // with black.  This seems to be related to an interaction between DWM and
-    // SetWindowRgn, but the details aren't clear. Additionally, we need to
-    // specify SWP_NOZORDER here, otherwise if you have multiple chrome windows
-    // open they will re-appear with a non-deterministic Z-order.
-    UINT flags = SWP_NOMOVE | SWP_NOSIZE | SWP_NOZORDER;
-    SetWindowPos(hwnd(), NULL, 0, 0, 0, 0, flags | SWP_HIDEWINDOW);
-    SetWindowPos(hwnd(), NULL, 0, 0, 0, 0, flags | SWP_SHOWWINDOW);
+  if (base::win::GetVersion() < base::win::VERSION_VISTA) {
+    // Don't redraw the window here, because we invalidate the window later.
+    ResetWindowRegion(true, false);
+    // The non-client view needs to update too.
+    delegate_->HandleFrameChanged();
+    InvalidateRect(hwnd(), NULL, FALSE);
+  } else {
+    dwm_transition_desired_ = true;

[sky, 2014/08/20 15:25:56]

Shouldn't this be conditional on whether you actually need a dwm frame?

[ananta, 2014/08/20 18:52:54]

Done.

+    // On Windows Vista and beyond, if we are transitioning from glass to

[sky, 2014/08/20 15:25:56]

I think this comment would be better in the header for dwm_transition_desired_.
That way there is a central place describing how all this works.

[ananta, 2014/08/20 18:52:54]

Done.

+    // custom and vice versa we delay setting the DWM related properties in
+    // full screen mode as DWM is not supported in full screen windows. We
+    // perform the DWM related operations when the window comes out of
+    // fullscreen mode.
+    if (!fullscreen_handler_->fullscreen())
+      PerformDwmTransition();
   }
-
-  // WM_DWMCOMPOSITIONCHANGED is only sent to top level windows, however we want
-  // to notify our children too, since we can have MDI child windows who need to
-  // update their appearance.
-  EnumChildWindows(hwnd(), &SendDwmCompositionChanged, NULL);
 }
 
 void HWNDMessageHandler::SchedulePaintInRect(const gfx::Rect& rect) {
   if (use_layered_buffer_) {
     // We must update the back-buffer immediately, since Windows' handling of
     // invalid rects is somewhat mysterious.
     invalid_rect_.Union(rect);
 
     // In some situations, such as drag and drop, when Windows itself runs a
     // nested message loop our message loop appears to be starved and we don't
@@ skipping 34 matching lines @@
   if (!app_icon.isNull()) {
     HICON windows_icon = IconUtil::CreateHICONFromSkBitmap(*app_icon.bitmap());
     HICON old_icon = reinterpret_cast<HICON>(
         SendMessage(hwnd(), WM_SETICON, ICON_BIG,
                     reinterpret_cast<LPARAM>(windows_icon)));
     if (old_icon)
       DestroyIcon(old_icon);
   }
 }
 
+void HWNDMessageHandler::SetFullscreen(bool fullscreen) {
+  fullscreen_handler()->SetFullscreen(fullscreen);
+  // If we are out of fullscreen and there was a pending DWM transition for the
+  // window, then go ahead and do it now.
+  if (!fullscreen && dwm_transition_desired_)
+    PerformDwmTransition();
+}
+
 ////////////////////////////////////////////////////////////////////////////////
 // HWNDMessageHandler, InputMethodDelegate implementation:
 
 void HWNDMessageHandler::DispatchKeyEventPostIME(const ui::KeyEvent& key) {
   SetMsgHandled(delegate_->HandleKeyEvent(key));
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 // HWNDMessageHandler, gfx::WindowImpl overrides:
 
@@ skipping 258 matching lines @@
     DeleteObject(new_region);
   }
 
   DeleteObject(current_rgn);
 }
 
 void HWNDMessageHandler::UpdateDwmNcRenderingPolicy() {
   if (base::win::GetVersion() < base::win::VERSION_VISTA)
     return;
 
+  if (fullscreen_handler_->fullscreen())
+    return;
+
   DWMNCRENDERINGPOLICY policy =
       custom_window_region_ || delegate_->IsUsingCustomFrame() ?
           DWMNCRP_DISABLED : DWMNCRP_ENABLED;
 
   DwmSetWindowAttribute(hwnd(), DWMWA_NCRENDERING_POLICY,
                         &policy, sizeof(DWMNCRENDERINGPOLICY));
 }
 
 LRESULT HWNDMessageHandler::DefWindowProcWithRedrawLock(UINT message,
                                                         WPARAM w_param,
@@ skipping 1270 matching lines @@
     ::ClientToScreen(hwnd(), &mouse_location);
     POINT cursor_pos = {0};
     ::GetCursorPos(&cursor_pos);
     if (memcmp(&cursor_pos, &mouse_location, sizeof(POINT)))
       return false;
     return true;
   }
   return false;
 }
 
+void HWNDMessageHandler::PerformDwmTransition() {
+  DCHECK(!fullscreen_handler_->fullscreen());
+  DCHECK(dwm_transition_desired_);
+
+  dwm_transition_desired_ = false;
+
+  UpdateDwmNcRenderingPolicy();
+  // Don't redraw the window here, because we need to hide and show the window
+  // which will also trigger a redraw.
+  ResetWindowRegion(true, false);
+  // The non-client view needs to update too.
+  delegate_->HandleFrameChanged();
+
+  if (IsVisible() && !delegate_->IsUsingCustomFrame()) {
+    // For some reason, we need to hide the window after we change from a custom
+    // frame to a native frame.  If we don't, the client area will be filled
+    // with black.  This seems to be related to an interaction between DWM and
+    // SetWindowRgn, but the details aren't clear. Additionally, we need to
+    // specify SWP_NOZORDER here, otherwise if you have multiple chrome windows
+    // open they will re-appear with a non-deterministic Z-order.
+    UINT flags = SWP_NOMOVE | SWP_NOSIZE | SWP_NOZORDER;
+    SetWindowPos(hwnd(), NULL, 0, 0, 0, 0, flags | SWP_HIDEWINDOW);
+    SetWindowPos(hwnd(), NULL, 0, 0, 0, 0, flags | SWP_SHOWWINDOW);
+  }
+  // WM_DWMCOMPOSITIONCHANGED is only sent to top level windows, however we want
+  // to notify our children too, since we can have MDI child windows who need to
+  // update their appearance.
+  EnumChildWindows(hwnd(), &SendDwmCompositionChanged, NULL);
+}
+
 }  // namespace views