clang-format: Slightly row back on r257257.

r257257 change the way clang-format enforces line breaks after a
templated type has been line-wrapped. This was to fix an incorrect line
break if BinPackParameters is set to false. However, it also leads to
an unwanted line break in a different case. Thus, for now, only do this
when BinPackParameters is false. This isn't ideal yet, but helps us
until we have a better solution.

With BinPackParameters:
Before:
  void fffffffffff(aaaaaaaaaaaaaaaaaaaaaaaaaaa<aaaaaaaaaaaaaaaaaaaaaaa,
                                               aaaaaaaaaa> aaaaaaaaaa);

After:
  void fffffffffff(
      aaaaaaaaaaaaaaaaaaaaaaaaaaa<aaaaaaaaaaaaaaaaaaaaaaa, aaaaaaaaaa>
          aaaaaaaaaa);

llvm-svn: 257325