Detach old frame on WebFrame::swap.

components/printing/renderer/print_web_view_helper.cc

Index: components/printing/renderer/print_web_view_helper.cc
diff --git a/components/printing/renderer/print_web_view_helper.cc b/components/printing/renderer/print_web_view_helper.cc
index ab65ed6f255d98276b33fc6e70e8d784fe36efcd..3c718b6da821882df5b556d803990cbef9ad2f08 100644
--- a/components/printing/renderer/print_web_view_helper.cc
+++ b/components/printing/renderer/print_web_view_helper.cc
@@ -592,7 +592,10 @@ class PrepareFrameAndViewForPrint : public blink::WebViewClient,
       blink::WebTreeScopeType scope,
       const blink::WebString& name,
       blink::WebSandboxFlags sandboxFlags);
+  // TODO(lfg): Remove this method once the blink patch lands.
   virtual void frameDetached(blink::WebFrame* frame);
+  virtual void frameDetached(blink::WebFrame* frame,
+                             blink::WebDetachReason reason);
 
  private:
   void CallOnReady();
@@ -743,6 +746,12 @@ blink::WebFrame* PrepareFrameAndViewForPrint::createChildFrame(
 }
 
 void PrepareFrameAndViewForPrint::frameDetached(blink::WebFrame* frame) {
+  frameDetached(frame, blink::WebDetachReason::Remove);
+}
+
+void PrepareFrameAndViewForPrint::frameDetached(blink::WebFrame* frame,
+                                                blink::WebDetachReason reason) {
+  DCHECK(reason == blink::WebDetachReason::Remove);
   if (frame->parent())
     frame->parent()->removeChild(frame);
   frame->close();