Add test for filtering of IPC messages when RenderFrameHost is swapped out.

This is a followup CL to add test for the actual fix of filtering IPCs from swapped out RFHs. I've fixed the state transitions in RVH, since we had an illegal one and fixed up the unit tests to account for that.

BUG=351815

Review URL: https://codereview.chromium.org/196133032

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@259466 0039d316-1c4b-4281-b951-d872f2087c98
4 files changed