Force a frame changed message (WM_NCCALCSIZE) to occur during settings change.

ui/views/win/hwnd_message_handler.cc

Index: ui/views/win/hwnd_message_handler.cc
diff --git a/ui/views/win/hwnd_message_handler.cc b/ui/views/win/hwnd_message_handler.cc
index 0cacffe4a76dfdde167943bf1f232f87736b9a76..aca31b8caa87c73cb301cde5480e5b02e69ecec4 100644
--- a/ui/views/win/hwnd_message_handler.cc
+++ b/ui/views/win/hwnd_message_handler.cc
@@ -1330,6 +1330,8 @@ void HWNDMessageHandler::OnDestroy() {
 void HWNDMessageHandler::OnDisplayChange(UINT bits_per_pixel,
                                          const gfx::Size& screen_size) {
   delegate_->HandleDisplayChange();
+  // Force a WM_NCCALCSIZE to occur to ensure that we handle auto hide
+  // taskbars correctly.
   SendFrameChanged();
 }
 
@@ -1988,6 +1990,13 @@ void HWNDMessageHandler::OnSettingChange(UINT flags, const wchar_t* section) {
       delegate_->HandleWorkAreaChanged();
     SetMsgHandled(FALSE);
   }
+
+  // If the work area is changing, then it could be as a result of the taskbar
+  // broadcasting the WM_SETTINGCHANGE message due to changes in auto hide
+  // settings, etc. Force a WM_NCCALCSIZE to occur to ensure that we handle
+  // this correctly.
+  if (flags == SPI_SETWORKAREA)
+    SendFrameChanged();
 }
 
 void HWNDMessageHandler::OnSize(UINT param, const gfx::Size& size) {