session_manager: Modify ACCELERATED_FLAGS for EGL/GLX
session_manager: Modify ACCELERATED_FLAGS for EGL/GLX

Modify session_manager_setup.sh to force
chrome to follow EGL/GLX rendering based
on egl flag defined selectively for a
specific overlay.

BUG=None
TEST=Build and boot till UI login screen
with S/W X11 Mesa libs on Ricochet overlay.
Build and boot till UI on Daisy.

Change-Id: I209fe1eac367e5a0163f79db6f9cdd6cba273416
Signed-off-by: abhinav <d73ef2279de6577f7bf081737ee47554bbb7dc82@chromium.org>
Signed-off-by: Arjun.K.V <3cf137aa7976396e2ad3baf3075610277863610f@samsung.com>
Reviewed-on: https://gerrit.chromium.org/gerrit/43033
Reviewed-by: Mike Frysinger <8f3f75c74bd5184edcfa6534cab3c13a00a2f794@chromium.org>
Commit-Queue: Katie Roberts-Hoffman <18b264b2ffd2bdd8a10fa2695b949fed75badc6b@chromium.org>
Reviewed-by: Katie Roberts-Hoffman <18b264b2ffd2bdd8a10fa2695b949fed75badc6b@chromium.org>
Tested-by: Katie Roberts-Hoffman <18b264b2ffd2bdd8a10fa2695b949fed75badc6b@chromium.org>

chadversary/chromiumos.platform.login_manager,chadversary/chromiumos.platform.login_manager,chadversary/chromiumos.platform.login_manager