reversion of patch for 92868, to repair severe regression (129827, a=drivers

git-svn-id: svn://10.0.0.236/trunk@116295 18797224-902f-48f8-a5cc-f745e15eee43

mozilla/layout/html/table/src/nsTableFrame.cpp

@@ -1756,6 +1756,39 @@ nsTableFrame::SetColumnDimensions(nsIPresContext* aPresContext,
 
 // SEC: TODO need to worry about continuing frames prev/next in flow for splitting across pages.
 
+// GetParentStyleContextProvider:
+//  The grandparent frame is he parent style context provider
+//  That is, the parent of the outerTableFrame is the frame that has our parent style context
+//  NOTE: if ther is a placeholder frame for the outer table, then we use its grandparent frame.
+//
+NS_IMETHODIMP 
+nsTableFrame::GetParentStyleContextProvider(nsIPresContext* aPresContext,
+                                            nsIFrame** aProviderFrame, 
+                                            nsContextProviderRelationship& aRelationship)
+{
+  NS_ASSERTION(aProviderFrame, "null argument aProviderFrame");
+  if (aProviderFrame) {
+    nsIFrame* f;
+    GetParent(&f);
+    NS_ASSERTION(f,"TableFrame has no parent frame");
+    if (f) {
+      // see if there is a placeholder frame representing our parent's place in the frame tree
+      // if there is, we get the parent of that frame as our surrogate grandparent
+      nsIFrame* placeholder = nsnull;
+      GetPlaceholderFor(*aPresContext,*f,&placeholder);
+      if (placeholder) {
+        f = placeholder;
+      } 
+      f->GetParent(&f);
+      NS_ASSERTION(f,"TableFrame has no grandparent frame");
+    }
+    // parent context provider is the grandparent frame
+    *aProviderFrame = f;
+    aRelationship = eContextProvider_Ancestor;
+  }
+  return ((aProviderFrame != nsnull) && (*aProviderFrame != nsnull)) ? NS_OK : NS_ERROR_FAILURE;
+}
+
 // XXX this could be made more general to handle row modifications that change the
 // table height, but first we need to scrutinize every Invalidate
 static void