Add extra slaves for PDFium master.
Add extra slaves for PDFium master.

R=dpranke@chromium.org
BUG=584529

Review URL: https://codereview.chromium.org/1675353003

git-svn-id: 239fca9b83025a0b6f823aeeca02ba5be3d9fd76@298651 0039d316-1c4b-4281-b951-d872f2087c98

eunchong/build,eunchong/build,eunchong/build,eunchong/build