Remove bad CallJavascriptFunctionUnsafe call from PrintPreviewUI

chrome/browser/printing/background_printing_manager.cc

Index: chrome/browser/printing/background_printing_manager.cc
diff --git a/chrome/browser/printing/background_printing_manager.cc b/chrome/browser/printing/background_printing_manager.cc
index 330ecb907e49b463e3e287048798c2e1f74f23bd..fd10907e4f1243722d7abb0e1bdef2f935f9f135 100644
--- a/chrome/browser/printing/background_printing_manager.cc
+++ b/chrome/browser/printing/background_printing_manager.cc
@@ -113,6 +113,11 @@ void BackgroundPrintingManager::DeletePreviewContentsForBrowserContext(
   }
 }
 
+void BackgroundPrintingManager::OnPrintRequestCancelled(
+    WebContents* preview_contents) {
+  DeletePreviewContents(preview_contents);
+}
+
 void BackgroundPrintingManager::DeletePreviewContents(
     WebContents* preview_contents) {
   auto i = printing_contents_map_.find(preview_contents);