Rename gyp variable use_titlecase_in_grd_files -> use_titlecase_in_grd

See tools/gyp/pylib/gyp/input.py:
"Sections mathing the regexp '_(dir|file|path)s?$' are also considered PathSections."

Standard gyp variables should not be named like this.

BUG=

Review URL: https://codereview.chromium.org/552203002

Cr-Commit-Position: refs/heads/master@{#294166}
1 file changed