NetEq4: Removing templatization for AudioMultiVector

This saves approx 6% runtime for neteq4_speed_test.
$ time out/Release/neteq4_speed_test --runtime_ms=50000000

BUG=1363
R=minyue@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/2320006

git-svn-id: http://webrtc.googlecode.com/svn/trunk@4885 4adac7df-926f-26a2-2b94-8c16560cd09d
diff --git a/webrtc/modules/audio_coding/neteq4/merge.h b/webrtc/modules/audio_coding/neteq4/merge.h
index bb81e20..f1f64e6 100644
--- a/webrtc/modules/audio_coding/neteq4/merge.h
+++ b/webrtc/modules/audio_coding/neteq4/merge.h
@@ -53,7 +53,7 @@
   // must have |num_channels_| elements.
   int Process(int16_t* input, size_t input_length,
               int16_t* external_mute_factor_array,
-              AudioMultiVector<int16_t>* output);
+              AudioMultiVector* output);
 
  private:
   static const int kMaxSampleRate = 48000;
@@ -95,7 +95,7 @@
   SyncBuffer* sync_buffer_;
   int16_t expanded_downsampled_[kExpandDownsampLength];
   int16_t input_downsampled_[kInputDownsampLength];
-  AudioMultiVector<int16_t> expanded_;
+  AudioMultiVector expanded_;
 
   DISALLOW_COPY_AND_ASSIGN(Merge);
 };