Fix findings of wvla-cxx-extension This CL fixes occurances of the wvla-cxx-extension warning in platform/gestures. This is a newly introduced warning in Clang and existing occurances in ChromeOS break compatibility with future releases of LLVM. BUG=b:316021385 TEST=emerge-atlas chromeos-base/gestures Change-Id: If0eb2999d8a5abc3a367dc1c863d53258804d721 Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/gestures/+/5160432 Reviewed-by: Harry Cutts <[email protected]> Commit-Queue: Ryan Beltran <[email protected]> Code-Coverage: Sean O'Brien <[email protected]> Tested-by: Ryan Beltran <[email protected]>