Merge to XFA: Remove some abstractions in fxjs_v8.h.

Conflicts:
  fpdfsdk/src/javascript/Document.cpp
  fpdfsdk/src/javascript/JS_Runtime.cpp
  fpdfsdk/src/jsapi/fxjs_v8.cpp

New:
  fpdfsdk/src/fpdfxfa/fpdfxfa_app.cpp

(cherry picked from commit 6df59849472958e7de96da6d9fc7b223b7c1f1c3)
Original Review URL: https://codereview.chromium.org/1332973002 .

R=thestig@chromium.org

Review URL: https://codereview.chromium.org/1334833003 .
29 files changed