Changed RefCountedStaticMemory() to accept a void pointer.

Using a void pointer saves lots of redundant casting.

Also added RefCountedMemory front_as<type> which saves typing by not having to
wrap each call with a reinterpret_cast<>.

Review URL: https://codereview.chromium.org/126103003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@250808 0039d316-1c4b-4281-b951-d872f2087c98
21 files changed