Add an ImageSymbol class to the PDB writer.

An ImageSymbol can write to the PDB symbol record stream a symbol that
associates a name and a type with a location in an image.

The symbol type must be one of S_LDATA32, S_GDATA32, S_PUB32,
S_LMANDATA or S_GMANDATA.

BUG=
R=chrisha@chromium.org, sebmarchand@chromium.org

Review URL: https://codereview.appspot.com/120970044

git-svn-id: http://sawbuck.googlecode.com/svn/trunk@2227 15e8cca8-e42c-11de-a347-f34a4f72eb7d
3 files changed