Fix link's hover state if the link under scrollbar

third_party/WebKit/Source/core/page/ChromeClient.cpp

Index: third_party/WebKit/Source/core/page/ChromeClient.cpp
diff --git a/third_party/WebKit/Source/core/page/ChromeClient.cpp b/third_party/WebKit/Source/core/page/ChromeClient.cpp
index c048b73d418e85bef4138ffef2e6bb2874b45f22..5184b74ece32c83f25e0dc7f5a9687388b6680df 100644
--- a/third_party/WebKit/Source/core/page/ChromeClient.cpp
+++ b/third_party/WebKit/Source/core/page/ChromeClient.cpp
@@ -151,13 +151,16 @@ bool ChromeClient::openJavaScriptPrompt(LocalFrame* frame,
 
 void ChromeClient::mouseDidMoveOverElement(LocalFrame& frame,
                                            const HitTestResult& result) {
-  if (result.innerNode() &&
+  if (!result.scrollbar() && result.innerNode() &&
       result.innerNode()->document().isDNSPrefetchEnabled())
     prefetchDNS(result.absoluteLinkURL().host());
 
   showMouseOverURL(result);
 
-  setToolTip(frame, result);
+  if (result.scrollbar())
+    clearToolTip(frame);
+  else
+    setToolTip(frame, result);
 }
 
 void ChromeClient::setToolTip(LocalFrame& frame, const HitTestResult& result) {