Linux: Fix type mismatch compile error (issue #1354).

git-svn-id: http://chromiumembedded.googlecode.com/svn/trunk/cef3@1807 5089003a-bbd8-11dd-ad1f-f1f9622dbc98
Add #ifndef guards to types in cef_build.h (issue #1336).

git-svn-id: http://chromiumembedded.googlecode.com/svn/trunk/cef3@1808 5089003a-bbd8-11dd-ad1f-f1f9622dbc98