The template system converts the actual struct type to an array of chars.
Make sure the alignment is kept by the compiler.

This fixes a lot of serialization-related HW tests, for example cctest test-serialize/Serialize.

BUG=
TEST=cctest test-serialize

Review URL: https://chromiumcodereview.appspot.com/9702114
Patch from Daniel Kalmar <kalmard@homejinni.com>.

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11240 ce2b1a6d-e550-0410-aec6-3dcde31c8c00