Prevent Adam GPU kernel crash when the variable has zero element.
Prevent Adam GPU kernel crash when the variable has zero element.

The Adam CPU kernel does not crash the whole program but GPU kernel would crash
the whole program. This change makes GPU kernel to do nothing in that case.

PiperOrigin-RevId: 385638126
Change-Id: I60adc45af34d02954783c5986c23a67a08a1f82d

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