[WK2] [GTK] Allow running the web process with an arbitrary prefix command
https://bugs.webkit.org/show_bug.cgi?id=123201

Reviewed by Carlos Garcia Campos.

Launch the web process using WEB_PROCESS_CMD_PREFIX as a
prefix. Useful for debugging the web process with gdb, valgrind,
etc.

* UIProcess/Launcher/ProcessLauncher.h:
* UIProcess/Launcher/gtk/ProcessLauncherGtk.cpp:
(WebKit::ProcessLauncher::launchProcess):
* UIProcess/gtk/WebProcessProxyGtk.cpp:
(WebKit::WebProcessProxy::platformGetLaunchOptions):

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@158105 268f45cc-cd09-0410-ab3c-d52691b4dbfc
Unreviewed, EFL gardening.

fast/canvas/webgl/drawingbuffer-test.html is passing on efl-wk2.
Move it to efl-wk1 TestExpectations file.

* platform/efl-wk1/TestExpectations:
* platform/efl/TestExpectations:

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@158106 268f45cc-cd09-0410-ab3c-d52691b4dbfc