Python: Remove globals from the generated C++ code.
Python: Remove globals from the generated C++ code.

To match changes in Chromium:
https://codereview.chromium.org/1885563005

katjoyce/certificate-transparency,taknira/certificate-transparency,pphaneuf/certificate-transparency,lexibrent/certificate-transparency,grandamp/certificate-transparency,grandamp/certificate-transparency,AlCutter/certificate-transparency,katjoyce/certificate-transparency,lexibrent/certificate-transparency,AlCutter/certificate-transparency,pphaneuf/certificate-transparency,eranmes/certificate-transparency,eranmes/certificate-transparency,katjoyce/certificate-transparency,katjoyce/certificate-transparency,phad/certificate-transparency,eranmes/certificate-transparency,AlCutter/certificate-transparency,lexibrent/certificate-transparency,eranmes/certificate-transparency,google/certificate-transparency,taknira/certificate-transparency,RJPercival/certificate-transparency,eranmes/certificate-transparency,pphaneuf/certificate-transparency,phad/certificate-transparency,google/certificate-transparency,katjoyce/certificate-transparency,RJPercival/certificate-transparency,grandamp/certificate-transparency,taknira/certificate-transparency,taknira/certificate-transparency,phad/certificate-transparency,taknira/certificate-transparency,AlCutter/certificate-transparency,AlCutter/certificate-transparency,phad/certificate-transparency,eranmes/certificate-transparency,katjoyce/certificate-transparency,google/certificate-transparency,AlCutter/certificate-transparency,taknira/certificate-transparency,taknira/certificate-transparency,AlCutter/certificate-transparency,eranmes/certificate-transparency,grandamp/certificate-transparency,katjoyce/certificate-transparency,pphaneuf/certificate-transparency,RJPercival/certificate-transparency,google/certificate-transparency,RJPercival/certificate-transparency,lexibrent/certificate-transparency