Merge to XFA: Pass IJS_Runtime, not IJS_Context, to native object constructors.

Original Review URL: https://codereview.chromium.org/1389163007 .
(cherry picked from commit 848a13b6777cbff8cc4aea3ab3d69eaa0b82ae6c)

Merge conflics in:
fpdfsdk/src/javascript/JS_Runtime.cpp
fpdfsdk/src/javascript/JS_Runtime_Stub.cpp
fpdfsdk/src/jsapi/fxjs_v8.cpp

R=thestig@chromium.org

Review URL: https://codereview.chromium.org/1394993006 .
21 files changed