Fix Windows build: std::signbit isn't defined for integral.
Fix Windows build: std::signbit isn't defined for integral.

This is a Windows STL defect, working around explicitly with SFINAE and
std::is_integral<>
PiperOrigin-RevId: 396670526
Change-Id: Iedb30c5185772487730b21a184eb352a1d85ed94

tensorflow/tensorflow-experimental_link_static_libraries_once,Intel-tensorflow/tensorflow,tensorflow/tensorflow-pywrap_saved_model,paolodedios/tensorflow,tensorflow/tensorflow,tensorflow/tensorflow-pywrap_saved_model,Intel-Corporation/tensorflow,paolodedios/tensorflow,Intel-Corporation/tensorflow,tensorflow/tensorflow-pywrap_tf_optimizer,tensorflow/tensorflow-pywrap_tf_optimizer,Intel-tensorflow/tensorflow,karllessard/tensorflow,paolodedios/tensorflow,Intel-tensorflow/tensorflow,karllessard/tensorflow,yongtang/tensorflow,tensorflow/tensorflow,tensorflow/tensorflow-experimental_link_static_libraries_once,Intel-Corporation/tensorflow,tensorflow/tensorflow-pywrap_saved_model,yongtang/tensorflow,Intel-tensorflow/tensorflow,tensorflow/tensorflow-pywrap_saved_model,Intel-tensorflow/tensorflow,tensorflow/tensorflow-pywrap_saved_model,tensorflow/tensorflow-pywrap_tf_optimizer,yongtang/tensorflow,yongtang/tensorflow,tensorflow/tensorflow-pywrap_tf_optimizer,tensorflow/tensorflow-experimental_link_static_libraries_once,tensorflow/tensorflow-pywrap_tf_optimizer,Intel-Corporation/tensorflow,tensorflow/tensorflow-pywrap_tf_optimizer,tensorflow/tensorflow-pywrap_saved_model,tensorflow/tensorflow-experimental_link_static_libraries_once,karllessard/tensorflow,tensorflow/tensorflow,tensorflow/tensorflow-pywrap_tf_optimizer,karllessard/tensorflow,paolodedios/tensorflow,tensorflow/tensorflow,gautam1858/tensorflow,tensorflow/tensorflow-experimental_link_static_libraries_once,karllessard/tensorflow,tensorflow/tensorflow,paolodedios/tensorflow,tensorflow/tensorflow-pywrap_saved_model,yongtang/tensorflow,gautam1858/tensorflow,Intel-tensorflow/tensorflow,Intel-Corporation/tensorflow,tensorflow/tensorflow-experimental_link_static_libraries_once,Intel-Corporation/tensorflow,Intel-tensorflow/tensorflow,paolodedios/tensorflow,yongtang/tensorflow,gautam1858/tensorflow,tensorflow/tensorflow,yongtang/tensorflow,karllessard/tensorflow,tensorflow/tensorflow-pywrap_tf_optimizer,yongtang/tensorflow,Intel-Corporation/tensorflow,Intel-tensorflow/tensorflow,tensorflow/tensorflow-pywrap_saved_model,paolodedios/tensorflow,gautam1858/tensorflow,tensorflow/tensorflow-pywrap_tf_optimizer,tensorflow/tensorflow-experimental_link_static_libraries_once,paolodedios/tensorflow,Intel-Corporation/tensorflow,karllessard/tensorflow,tensorflow/tensorflow,karllessard/tensorflow,paolodedios/tensorflow,tensorflow/tensorflow-experimental_link_static_libraries_once,paolodedios/tensorflow,tensorflow/tensorflow-pywrap_saved_model,yongtang/tensorflow,gautam1858/tensorflow,gautam1858/tensorflow,gautam1858/tensorflow,tensorflow/tensorflow-experimental_link_static_libraries_once,tensorflow/tensorflow,tensorflow/tensorflow-pywrap_saved_model,gautam1858/tensorflow,paolodedios/tensorflow,gautam1858/tensorflow,karllessard/tensorflow,gautam1858/tensorflow,tensorflow/tensorflow,tensorflow/tensorflow,Intel-tensorflow/tensorflow,tensorflow/tensorflow-experimental_link_static_libraries_once,Intel-tensorflow/tensorflow,karllessard/tensorflow,tensorflow/tensorflow-pywrap_tf_optimizer,tensorflow/tensorflow,gautam1858/tensorflow,tensorflow/tensorflow-experimental_link_static_libraries_once,tensorflow/tensorflow-pywrap_tf_optimizer,tensorflow/tensorflow-pywrap_saved_model,yongtang/tensorflow,Intel-tensorflow/tensorflow,gautam1858/tensorflow,karllessard/tensorflow,yongtang/tensorflow