Merge to XFA: Rename Init methods to more accurately describe purpose

(cherry picked from commit df4de98c06075b0e491ac645f2d118a6813cedc9)
Trivial manual merges in
  fpdfsdk/include/javascript/JS_Runtime.h
  fpdfsdk/src/javascript/JS_Runtime.cpp

Original Review URL: https://codereview.chromium.org/1335763002 .

TBR=thestig@chromium.org

Review URL: https://codereview.chromium.org/1334313002 .
5 files changed