Revert "Add a compiler option to prune unused function and prototypes" Compile error on Mac: http://build.chromium.org/p/chromium.gpu.fyi/builders/GPU%20Mac%20Builder/builds/29051 This reverts commit e423d9ca6e1b340ae06d543419b8a515de5ac3f2. Change-Id: Ie08d7f2bf86089a006f3177480aa7491a9405257 Reviewed-on: https://chromium-review.googlesource.com/264585 Reviewed-by: Jamie Madill <jmadill@chromium.org> Tested-by: Jamie Madill <jmadill@chromium.org>