Middle-click to close tabs activates even if mouse-up is not over tab....

chrome/browser/views/tabs/tab.cc

Index: chrome/browser/views/tabs/tab.cc
===================================================================
--- chrome/browser/views/tabs/tab.cc	(revision 6115)
+++ chrome/browser/views/tabs/tab.cc	(working copy)
@@ -156,8 +156,8 @@
   // Notify the drag helper that we're done with any potential drag operations.
   // Clean up the drag helper, which is re-created on the next mouse press.
   delegate_->EndDrag(canceled);
-  if (event.IsMiddleMouseButton())
-    delegate_->CloseTab(this);
+  if (event.IsMiddleMouseButton() && HitTest(event.location()))
+      delegate_->CloseTab(this);
 }
 
 bool Tab::GetTooltipText(int x, int y, std::wstring* tooltip) {