re-enable parent window of modal dialog before dialog is destroyed. part of bug 28467. r=saari a=jar

xpfe/appshell/src/nsXULWindow.cpp

@@ -877,11 +877,11 @@ NS_IMETHODIMP nsXULWindow::ShowModal()
    appShell->Spinup();
    // Store locally so it doesn't die on us
    nsCOMPtr<nsIWidget> window = mWindow;
-   nsCOMPtr<nsIXULWindow> tempRef = this;  
-                                          
+   nsCOMPtr<nsIXULWindow> tempRef = this;
 
    window->SetModal(PR_TRUE);
    mContinueModalLoop = PR_TRUE;
+   EnableParent(PR_FALSE);
 
    nsCOMPtr<nsIJSContextStack> stack(do_GetService("nsThreadJSContextStack"));
    nsresult rv = NS_OK;
@@ -918,6 +918,8 @@ NS_IMETHODIMP nsXULWindow::ShowModal()
 
 NS_IMETHODIMP nsXULWindow::ExitModalLoop()
 {
+   if (mContinueModalLoop) // was a modal window
+     EnableParent(PR_TRUE);
    mContinueModalLoop = PR_FALSE;
    return NS_OK;
 }
@@ -1072,6 +1074,18 @@ NS_IMETHODIMP nsXULWindow::NotifyObservers(const PRUnichar* aTopic,
    return NS_OK;
 }
 
+void nsXULWindow::EnableParent(PRBool aEnable)
+{
+  nsCOMPtr<nsIBaseWindow> parentWindow;
+  nsCOMPtr<nsIWidget>     parentWidget;
+
+  parentWindow = do_QueryReferent(mParentWindow);
+  if (parentWindow)
+    parentWindow->GetMainWidget(getter_AddRefs(parentWidget));
+  if (parentWidget)
+    parentWidget->Enable(aEnable);
+}
+
 //*****************************************************************************
 // nsXULWindow: Accessors
 //*****************************************************************************

xpfe/appshell/src/nsXULWindow.h

@@ -31,6 +31,7 @@
 #include "nsCOMPtr.h"
 #include "nsVoidArray.h"
 #include "nsString.h"
+#include "nsWeakReference.h"
 
 // Interfaces needed
 #include "nsIBaseWindow.h"
@@ -44,7 +45,8 @@
 // nsXULWindow
 
 class nsXULWindow : public nsIXULWindow, public nsIBaseWindow, 
-   public nsIInterfaceRequestor
+   public nsIInterfaceRequestor,
+   public nsSupportsWeakReference
 {
 friend class nsChromeTreeOwner;
 friend class nsContentTreeOwner;
@@ -86,11 +88,14 @@ protected:
    NS_IMETHOD NotifyObservers(const PRUnichar* aTopic, const PRUnichar* aData);
 
 protected:
+   void EnableParent(PRBool aEnable);
+
    nsChromeTreeOwner*      mChromeTreeOwner;
    nsContentTreeOwner*     mContentTreeOwner;
    nsContentTreeOwner*     mPrimaryContentTreeOwner;
    nsCOMPtr<nsIWidget>     mWindow;
    nsCOMPtr<nsIDocShell>   mDocShell;
+   nsCOMPtr<nsIWeakReference> mParentWindow;
    nsVoidArray             mContentShells;
    PRBool                  mContinueModalLoop;
    PRBool                  mDebuting;       // being made visible right now