- Removed the BitfieldMap class because it is unnecessary.
We now just track the most recently added field.
- Moved the code that calculates bitfield widths so it
can also be used to determine whether it's necessary
to insert anonymous fields.
- Simplified the anonymous field calculation code into
three cases (two of which are resolved identically).
- Beefed up the bitfield testcase.
llvm-svn: 169449