Merge to XFA: Add a missing #include that's needed for call to FXSYS_tolower.

TBR=dml@google.com

Review URL: https://codereview.chromium.org/1329343002.

(cherry picked from commit 8ad46d3d6829d879cd342caec4c6f7eaae43cba0)

Review URL: https://codereview.chromium.org/1346843005 .
1 file changed