Add specializations for a few more types in the IPC fuzzer.

Also deal with one more guarded message file.
R=aedla@chromium.org
BUG=

Review URL: https://codereview.chromium.org/129873020

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@246521 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 246521