Bug 1006765: Ensure that Win32 widget handles terminal services messages; r=jimm

--HG--
extra : rebase_source : a25ad41fb20aa3b52207a78f42d51fb870246bf4

toolkit/library/libxul.mk

@@ -207,7 +207,7 @@ OS_LIBS += $(call EXPAND_LIBNAME,util)
 endif
 
 ifeq ($(OS_ARCH),WINNT)
-OS_LIBS += $(call EXPAND_LIBNAME,shell32 ole32 version winspool comdlg32 imm32 msimg32 shlwapi psapi ws2_32 dbghelp rasapi32 rasdlg iphlpapi uxtheme setupapi secur32 sensorsapi portabledeviceguids windowscodecs wininet wbemuuid wintrust)
+OS_LIBS += $(call EXPAND_LIBNAME,shell32 ole32 version winspool comdlg32 imm32 msimg32 shlwapi psapi ws2_32 dbghelp rasapi32 rasdlg iphlpapi uxtheme setupapi secur32 sensorsapi portabledeviceguids windowscodecs wininet wbemuuid wintrust wtsapi32)
 ifdef ACCESSIBILITY
 OS_LIBS += $(call EXPAND_LIBNAME,oleacc)
 endif

widget/windows/nsWindow.cpp

@@ -66,6 +66,7 @@
 
 #include <shellapi.h>
 #include <windows.h>
+#include <wtsapi32.h>
 #include <process.h>
 #include <commctrl.h>
 #include <unknwn.h>
@@ -606,6 +607,14 @@ nsWindow::Create(nsIWidget *aParent,
 
   SubclassWindow(TRUE);
 
+  // Starting with Windows XP, a process always runs within a terminal services
+  // session. In order to play nicely with RDP, fast user switching, and the
+  // lock screen, we should be handling WM_WTSSESSION_CHANGE. We must register
+  // our HWND in order to receive this message.
+  DebugOnly<BOOL> wtsRegistered = ::WTSRegisterSessionNotification(mWnd,
+                                                       NOTIFY_FOR_THIS_SESSION);
+  NS_ASSERTION(wtsRegistered, "WTSRegisterSessionNotification failed!\n");
+
   IMEHandler::InitInputContext(this, mInputContext);
 
   // If the internal variable set by the config.trim_on_minimize pref has not
@@ -4569,6 +4578,21 @@ nsWindow::ProcessMessage(UINT msg, WPARAM& wParam, LPARAM& lParam,
     }
     break;
 
+    case WM_WTSSESSION_CHANGE:
+    {
+      switch (wParam) {
+        case WTS_CONSOLE_CONNECT:
+        case WTS_REMOTE_CONNECT:
+        case WTS_SESSION_UNLOCK:
+          // When a session becomes visible, we should invalidate.
+          Invalidate(true, true, true);
+          break;
+        default:
+          break;
+      }
+    }
+    break;
+
     case WM_FONTCHANGE:
     {
       // We only handle this message for the hidden window,
@@ -6401,6 +6425,9 @@ void nsWindow::OnDestroy()
   mWidgetListener = nullptr;
   mAttachedWidgetListener = nullptr;
 
+  // Unregister notifications from terminal services
+  ::WTSUnRegisterSessionNotification(mWnd);
+
   // Free our subclass and clear |this| stored in the window props. We will no longer
   // receive events from Windows after this point.
   SubclassWindow(FALSE);