Delete document marker related invalidation code.

sky/engine/public/web/WebWidgetClient.h

Index: sky/engine/public/web/WebWidgetClient.h
diff --git a/sky/engine/public/web/WebWidgetClient.h b/sky/engine/public/web/WebWidgetClient.h
index 3d9fa023900f7a2781bc65807a1b54a1d03e5e7e..95ae5aab5c84eb83fbd2bc4624f117e840806ab9 100644
--- a/sky/engine/public/web/WebWidgetClient.h
+++ b/sky/engine/public/web/WebWidgetClient.h
@@ -103,9 +103,6 @@ public:
     virtual WebRect windowRect() { return WebRect(); }
     virtual void setWindowRect(const WebRect&) { }
 
-    // Called when a tooltip should be shown at the current cursor position.
-    virtual void setToolTipText(const WebString&, WebTextDirection hint) { }
-
     // Called to get the position of the resizer rect in window coordinates.
     virtual WebRect windowResizerRect() { return WebRect(); }