Bug #122500 --> make sure the mail window comes to the front of all apps even if it's

minimized if the user double clicks the mail icon. Make sure the double click
works on optimized bits by using a static string for "mail:3pane"

r=bhuvan
sr=bienvenu

mailnews/base/src/nsMessengerWinIntegration.cpp

@@ -57,6 +57,11 @@
 
 #include "nsIWindowMediator.h"
 #include "nsIDOMWindowInternal.h"
+#include "nsIScriptGlobalObject.h"
+#include "nsIDocShell.h"
+#include "nsIBaseWindow.h"
+#include "nsIWidget.h"
+
 #include "nsIMessengerWindowService.h"
 #include "prprf.h"
 #include "nsIWeakReference.h"
@@ -78,6 +83,40 @@
 #undef GetUserName
 #endif
 
+// begin shameless copying from nsNativeAppSupportWin
+HWND hwndForDOMWindow( nsISupports *window ) 
+{
+  nsCOMPtr<nsIScriptGlobalObject> ppScriptGlobalObj( do_QueryInterface(window) );
+  if ( !ppScriptGlobalObj )
+      return 0;
+  nsCOMPtr<nsIDocShell> ppDocShell;
+  ppScriptGlobalObj->GetDocShell( getter_AddRefs( ppDocShell ) );
+  if ( !ppDocShell ) return 0;
+  
+  nsCOMPtr<nsIBaseWindow> ppBaseWindow( do_QueryInterface( ppDocShell ) );
+  if (!ppBaseWindow) return 0;
+
+  nsCOMPtr<nsIWidget> ppWidget;
+  ppBaseWindow->GetMainWidget( getter_AddRefs( ppWidget ) );
+
+  return (HWND)( ppWidget->GetNativeData( NS_NATIVE_WIDGET ) );
+}
+
+static void activateWindow( nsIDOMWindowInternal *win ) 
+{
+  // Try to get native window handle.
+  HWND hwnd = hwndForDOMWindow( win );
+  if ( hwnd ) 
+  {
+    // Restore the window if it is minimized.
+    if ( ::IsIconic( hwnd ) ) 
+      ::ShowWindow( hwnd, SW_RESTORE );
+    // Use the OS call, if possible.
+    ::SetForegroundWindow( hwnd );
+  } else // Use internal method.  
+    win->Focus();
+}
+// end shameless copying from nsNativeAppWinSupport.cpp
 
 // Message window encapsulation.
 struct MessageWindow 
@@ -86,6 +125,8 @@ struct MessageWindow
     MessageWindow() 
     {
       Create();
+      // dummy code to force creation of our string
+      const char * fakeName = mailWinName();
     }
 
     // Act like an HWND.
@@ -94,6 +135,23 @@ struct MessageWindow
         return mHandle;
     }
 
+    // for some reason WindowProc can't access the string literal "mail:3pane", we need to copy that string
+    // into a static buffer outside of the WindowProc call. 
+    static const char * mailWinName()
+    {
+      static char mailNameBuffer[128];
+      static char *mMailWinName = 0;
+      if ( !mMailWinName ) 
+      {
+        ::_snprintf( mailNameBuffer,
+                     sizeof mailNameBuffer,
+                     "%s",
+                     "mail:3pane" );
+        mMailWinName = mailNameBuffer;
+      }
+      return mMailWinName;
+    }
+
     // Class name: appName + "MessageWindow"
     static const char *className() 
     {
@@ -156,9 +214,12 @@ struct MessageWindow
            if (mediator)
            {
              nsCOMPtr<nsIDOMWindowInternal> domWindow;
-             mediator->GetMostRecentWindow( NS_LITERAL_STRING("mail:3pane").get(), getter_AddRefs(domWindow));
+             nsAutoString mailName;
+             mailName.AssignWithConversion(mailWinName());
+
+             mediator->GetMostRecentWindow( mailName.get(), getter_AddRefs(domWindow));
              if (domWindow)
-               domWindow->Focus();
+               activateWindow(domWindow);
              else
              {
                // the user doesn't have a mail window open already so open one for them...