Added debug asserts to present windows. This will hopefully cause KWin

to crash instead of producing black screens making it easier to find the
cause. For the people who can reproduce existing crashes please resubmit
their backtraces with this change applied.
CCBUG: 185127
CCBUG: 185239

svn path=/trunk/KDE/kdebase/workspace/; revision=933187

effects/presentwindows/presentwindows.cpp

@@ -173,6 +173,8 @@ void PresentWindowsEffect::prePaintWindow( EffectWindow *w, WindowPrePaintData &
         w->enablePainting( EffectWindow::PAINT_DISABLED_BY_MINIMIZE ); // Display always
         w->enablePainting( EffectWindow::PAINT_DISABLED_BY_DESKTOP );
 
+        assert( m_windowData.contains( w ));
+
         // Calculate window's opacity
         // TODO: Minimized windows or windows not on the current desktop are only 75% visible?
         if( m_windowData[w].visible )
@@ -211,6 +213,9 @@ void PresentWindowsEffect::paintWindow( EffectWindow *w, int mask, QRegion regio
             effects->paintWindow( w, mask, region, data );
             return;
             }
+
+        assert( m_windowData.contains( w ));
+
         // Apply opacity and brightness
         data.opacity *= m_windowData[w].opacity;
         data.brightness *= interpolate( 0.7, 1.0, m_windowData[w].highlight );
@@ -275,6 +280,7 @@ void PresentWindowsEffect::windowClosed( EffectWindow *w )
         return;
     if( m_highlightedWindow == w )
         setHighlightedWindow( findFirstWindow() );
+    assert( m_windowData.contains( w ));
     m_windowData[w].visible = false; // TODO: Fix this so they do actually fade out
     }
 
@@ -282,6 +288,7 @@ void PresentWindowsEffect::windowDeleted( EffectWindow *w )
     {
     if( !m_activated )
         return;
+    assert( m_windowData.contains( w ));
     delete m_windowData[w].textFrame;
     delete m_windowData[w].iconFrame;
     m_windowData.remove( w );
@@ -311,6 +318,7 @@ void PresentWindowsEffect::windowInputMouseEvent( Window w, QEvent *e )
     EffectWindowList windows = m_motionManager.managedWindows();
     for( int i = 0; i < windows.size(); i++ )
         {
+        assert( m_windowData.contains( windows.at( i )));
         if( m_motionManager.transformedGeometry( windows.at( i )).contains( cursorPos() ) &&
             m_windowData[windows.at( i )].visible )
             {
@@ -468,6 +476,7 @@ void PresentWindowsEffect::rearrangeWindows()
         foreach( EffectWindow *w, m_motionManager.managedWindows() )
             {
             windowlists[w->screen()].append( w );
+            assert( m_windowData.contains( w ));
             m_windowData[w].visible = true;
             }
         }
@@ -475,6 +484,7 @@ void PresentWindowsEffect::rearrangeWindows()
         { // Can we move this filtering somewhere else?
         foreach( EffectWindow *w, m_motionManager.managedWindows() )
             {
+            assert( m_windowData.contains( w ));
             if( w->caption().contains( m_windowFilter, Qt::CaseInsensitive ) ||
                 w->windowClass().contains( m_windowFilter, Qt::CaseInsensitive ) ||
                 w->windowRole().contains( m_windowFilter, Qt::CaseInsensitive ))
@@ -496,6 +506,7 @@ void PresentWindowsEffect::rearrangeWindows()
     // We filtered out the highlighted window
     if( m_highlightedWindow )
         {
+        assert( m_windowData.contains( m_highlightedWindow ));
         if( m_windowData[m_highlightedWindow].visible == false )
             setHighlightedWindow( findFirstWindow() );
         }
@@ -1162,6 +1173,7 @@ void PresentWindowsEffect::setActive( bool active, bool closingTab )
             foreach( EffectWindow *w, effects->currentTabBoxWindowList() )
                 {
                 m_motionManager.manage( w );
+                assert( m_windowData.contains( w ));
                 m_windowData[w].visible = effects->currentTabBoxWindowList().contains( w );
                 }
             // Hide windows not in the list
@@ -1214,6 +1226,7 @@ void PresentWindowsEffect::setActive( bool active, bool closingTab )
         // Fade in/out all windows
         foreach( EffectWindow *w, effects->stackingOrder() )
             {
+            assert( m_windowData.contains( w ));
             EffectWindow *activeWindow = effects->activeWindow();
             if( m_tabBoxEnabled )
                 activeWindow = effects->currentTabBoxWindow();