The counting is moved to NetEqImpl, and the new counter is realized as a Stopwatch object. The DecisionLogic class still has to maintain record of when the CNG period is shortened, in order to reduce the delay. This is recorded in a new noise_fast_forward_ member in DecisionLogic. BUG=webrtc:5608 Review-Url: https://codereview.webrtc.org/1914303004 Cr-Commit-Position: refs/heads/master@{#12608}