Use Resampler default constructor in VAD

Review URL: https://codereview.webrtc.org/1224693013

Cr-Commit-Position: refs/heads/master@{#9551}
diff --git a/webrtc/modules/audio_processing/vad/voice_activity_detector.cc b/webrtc/modules/audio_processing/vad/voice_activity_detector.cc
index b39ed66..05995ed 100644
--- a/webrtc/modules/audio_processing/vad/voice_activity_detector.cc
+++ b/webrtc/modules/audio_processing/vad/voice_activity_detector.cc
@@ -28,8 +28,6 @@
 
 VoiceActivityDetector::VoiceActivityDetector()
     : last_voice_probability_(kDefaultVoiceValue),
-      // Initialize to the most common resampling situation.
-      resampler_(kMaxLength, kLength10Ms, kNumChannels),
       standalone_vad_(StandaloneVad::Create()) {
 }