Make WebSpellCheckClient aware of leak detection

third_party/WebKit/public/web/WebSpellCheckClient.h

Index: third_party/WebKit/public/web/WebSpellCheckClient.h
diff --git a/third_party/WebKit/public/web/WebSpellCheckClient.h b/third_party/WebKit/public/web/WebSpellCheckClient.h
index bbbd547f682f3e128e5369d1cf8a40126f3a70bc..77c4dfb467e0f049965f58d9cb3643a4e69bf2a0 100644
--- a/third_party/WebKit/public/web/WebSpellCheckClient.h
+++ b/third_party/WebKit/public/web/WebSpellCheckClient.h
@@ -67,6 +67,10 @@ public:
                                        const WebVector<unsigned>& markerOffsets,
                                        WebTextCheckingCompletion* completionCallback) { }
 
+    // Clear all stored references to requests, so that it will not become a
+    // leak source.
+    virtual void cancelAllPendingRequests() { }
+
     // Show or hide the spelling UI.
     virtual void showSpellingUI(bool show) { }