Merging r311456:

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r311456 | krasimir | 2017-08-22 07:28:01 -0700 (Tue, 22 Aug 2017) | 13 lines

[clang-format] Fix lines regression in clang-format.py

Summary:
This patch fixes a regression after https://reviews.llvm.org/rL305665,
which updates the structure of the `lines` variable.

Reviewers: djasper

Reviewed By: djasper

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D37011
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llvm-svn: 319179