Export Sanitizer Fixes, 1.0 branch (2019.12.11.)

This MR is a distillation of !572 (merged), !575 (merged) and !577 (merged) into a single update, for the 1.0 branch.

It makes sure that the project-specific export sanitizer scripts would be used when building the external projects. So that when/if something fails to build, the exported CMake configurations of the projects would still be usable for building downstream projects.

AE Build SUCCESS
Build logfiles are available at Jenkins [AE-MERGE-REQUEST #877]

merged

mentioned in commit 12ae0be3