Fix frame tree mangling when a combobox is inside a pseudo-cell. Bug 275746,

r=bernd, sr=roc


git-svn-id: svn://10.0.0.236/trunk@168661 18797224-902f-48f8-a5cc-f745e15eee43

mozilla/layout/base/nsCSSFrameConstructor.cpp

@@ -4806,10 +4806,24 @@ nsCSSFrameConstructor::ConstructSelectFrame(nsIPresShell*        aPresShell,
       // Create display and button frames from the combobox's anonymous content.
       // The anonymous content is appended to existing anonymous content for this
       // element (the scrollbars).
+
+      // save the incoming pseudo frame state, so that we don't end up
+      // with those pseudoframes in childItems
+      nsPseudoFrames priorPseudoFrames; 
+      aState.mPseudoFrames.Reset(&priorPseudoFrames);
+
       nsFrameItems childItems;
       CreateAnonymousFrames(aPresShell, aPresContext, nsHTMLAtoms::combobox,
                             aState, aContent, comboboxFrame, PR_TRUE, childItems);
   
+      // process the current pseudo frame state
+      if (!aState.mPseudoFrames.IsEmpty()) {
+        ProcessPseudoFrames(aPresContext, aState.mPseudoFrames, childItems);
+      }
+
+      // restore the incoming pseudo frame state 
+      aState.mPseudoFrames = priorPseudoFrames;
+      
       comboboxFrame->SetInitialChildList(aPresContext, nsnull,
                                          childItems.childList);