Sync patch r15356 from main trunk.
Force UID modules build error to warn user that currently it is just a sample.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Jeff Fan <jeff.fan@intel.com>

git-svn-id: https://svn.code.sf.net/p/edk2/code/branches/UDK2010.SR1@15358 6f19259b-4bc3-4df7-8a09-765794883524
Sync patch r15357 from main trunk.
MdeModulePkg PCD: Fix PCD driver to return default data if size mismatch.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Jeff Fan <jeff.fan@intel.com>

git-svn-id: https://svn.code.sf.net/p/edk2/code/branches/UDK2010.SR1@15359 6f19259b-4bc3-4df7-8a09-765794883524