Remove homebrew List implementation

Use std::list instead of gestures::List
Include helper function where needed for .at needs
Changed LookaheadFilterInterpreter::free_list_ to be a vector
Added QStateList test for coverage improvement

BUG=b:270612476
TEST=USE="coverage" FEATURES="test noclean" emerge-brya chromeos-base/gestures

Change-Id: I0857ff48f8d386f15b887d25349c734f2710f946
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/gestures/+/4303073
Auto-Submit: Denis Brockus <dbrockus@chromium.org>
Code-Coverage: Henry Barnor <hbarnor@chromium.org>
Commit-Queue: Denis Brockus <dbrockus@chromium.org>
Reviewed-by: Harry Cutts <hcutts@chromium.org>
Tested-by: Denis Brockus <dbrockus@chromium.org>
9 files changed