Enable ClangTidy check misc-definitions-in-headers.

https://clang.llvm.org/extra/clang-tidy/checks/misc-definitions-in-headers.html

Finds non-extern non-inline function and variable definitions in header
files, which can lead to potential ODR violations in case these headers
are included from multiple translation units.

Change-Id: I5a80d8bddbc7fae97a3b714ac4e376bcefc3b060
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/307436
Commit-Queue: John Stiles <johnstiles@google.com>
Auto-Submit: John Stiles <johnstiles@google.com>
Reviewed-by: Mike Klein <mtklein@google.com>
2 files changed