implement GetScreenBounds, which wasn't, oddly. this should fix placement of top-level windows which, equally oddly, seemed unbroken except in one very esoteric circumstance. bug 233081 r=ere,roc

widget/src/windows/nsWindow.cpp

@@ -2282,7 +2282,23 @@ void nsWindow::GetNonClientBounds(nsRect &aRect)
   }
 }
 
-           
+// like GetBounds, but don't offset by the parent
+NS_METHOD nsWindow::GetScreenBounds(nsRect &aRect)
+{
+  if (mWnd) {
+    RECT r;
+    VERIFY(::GetWindowRect(mWnd, &r));
+
+    aRect.width  = r.right - r.left;
+    aRect.height = r.bottom - r.top;
+    aRect.x = r.left;
+    aRect.y = r.top;
+  } else
+    aRect = mBounds;
+
+  return NS_OK;
+}
+
 //-------------------------------------------------------------------------
 //
 // Set the background color

widget/src/windows/nsWindow.h

@@ -336,6 +336,7 @@ public:
     NS_IMETHOD              SetFocus(PRBool aRaise);
     NS_IMETHOD              GetBounds(nsRect &aRect);
     NS_IMETHOD              GetClientBounds(nsRect &aRect);
+    NS_IMETHOD              GetScreenBounds(nsRect &aRect);
     NS_IMETHOD              SetBackgroundColor(const nscolor &aColor);
     virtual nsIFontMetrics* GetFont(void);
     NS_IMETHOD              SetFont(const nsFont &aFont);