hg: openjfx/8u-dev/rt: 8194935: Cherry pick GTK WebKit 2.18.5 changes

[arunprasad.rajkumar at oracle.com]

Changeset: 00c154c7b9d7
Author:    arajkumar
Date:      2018-01-20 23:05 +0530
URL:       http://hg.openjdk.java.net/openjfx/8u-dev/rt/rev/00c154c7b9d7

8194935: Cherry pick GTK WebKit 2.18.5 changes
Reviewed-by: mbilla, kcr

! modules/web/src/main/native/Source/JavaScriptCore/runtime/JSGlobalObject.cpp
! modules/web/src/main/native/Source/JavaScriptCore/runtime/JSGlobalObject.h
! modules/web/src/main/native/Source/WTF/wtf/Platform.h
! modules/web/src/main/native/Source/WebCore/Modules/mediastream/libwebrtc/LibWebRTCMediaEndpoint.cpp
! modules/web/src/main/native/Source/WebCore/page/Performance.cpp
! modules/web/src/main/native/Source/cmake/OptionsGTK.cmake
! modules/web/src/main/native/Tools/gtk/gtkdoc.py