Merge to XFA: Remove some checks for object creation failures. They cannot fail.

Also reduce nesting in if statements, remove CFX_SmartPointer, and
use more unique_ptrs.

TBR=tsepez@chromium.org

Review URL: https://codereview.chromium.org/1393303004 .

(cherry picked from commit 6101a5f98b27888f1736ae74982ed4d409d83be0)

Review URL: https://codereview.chromium.org/1413223002 .
2 files changed