Add WebContents source to methods in WebContentsDelegate

chrome/browser/prerender/prerender_contents.cc

Index: chrome/browser/prerender/prerender_contents.cc
diff --git a/chrome/browser/prerender/prerender_contents.cc b/chrome/browser/prerender/prerender_contents.cc
index b1d8cf10476af13b011d6451da2f562440bebe44..4a55361526f5773fe99173240349d5e7f8bd4d3a 100644
--- a/chrome/browser/prerender/prerender_contents.cc
+++ b/chrome/browser/prerender/prerender_contents.cc
@@ -171,7 +171,7 @@ class PrerenderContents::WebContentsDelegateImpl
     return false;
   }
 
-  bool ShouldSuppressDialogs() override {
+  bool ShouldSuppressDialogs(WebContents* source) override {
     // We still want to show the user the message when they navigate to this
     // page, so cancel this prerender.
     prerender_contents_->Destroy(FINAL_STATUS_JAVASCRIPT_ALERT);