[clang-format] Add more tests for ObjC protocol list formatting behavior

[clang-format] Add more tests for ObjC protocol list formatting behavior

Summary:
The existing unit tests in FormatTestObjC.cpp didn't fully cover
all the cases for protocol confirmance list formatting.

This extends the unit tests to more cases of protocol
conformance list formatting, especially how the behavior changes
when `BinPackParameters` changes from `true` (the default) to `false`.

Test Plan: make -j12 FormatTests && \
  ./tools/clang/unittests/Format/FormatTests --gtest_filter=FormatTestObjC.\*

Reviewers: krasimir, jolesiak, stephanemoore

Reviewed By: krasimir

Subscribers: benhamilton, klimek, cfe-commits, hokein, Wizard

Differential Revision: https://reviews.llvm.org/D42649

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@323684 91177308-0d34-0410-b5e6-96231b3b80d8