Enable bin-packing in Google style.

After some discussions, it seems that this is the better path in
the long run. Does not change Chromium style, as there, bin packing
is forbidden by the style guide.

Also fix two minor bugs wrt. formatting:
1. If a call parameter is a function call itself and is split before
   the "." or "->", split before the next parameter.
2. If a call parameter is string literal that has to be split onto
   two lines, split before the next parameter.

git-svn-id: http://llvm.org/svn/llvm-project/cfe/trunk@176177 91177308-0d34-0410-b5e6-96231b3b80d8