facebook/hhvm — pull request #4120 by aingram (2014-11-02 05:38:19+00:00)
Title: Added CallerFrame before call to xmlXPathEvalExpression

Added CallerFrame before dom_xpath_ext_function_php's call to xmlXPathEvalExpression in case libxml2 needs to call back into HHVM.
The xpath query might contain "php:functionString" which triggers a call to any arbitrary php function.
Partially fixes #4116