Move functionality out from AudioFrame and into AudioFrameOperations.

webrtc/audio/utility/BUILD.gn

 # Copyright (c) 2016 The WebRTC project authors. All Rights Reserved.
 #
 # Use of this source code is governed by a BSD-style license
 # that can be found in the LICENSE file in the root of the source
 # tree. An additional intellectual property rights grant can be found
 # in the file PATENTS.  All contributing project authors may
 # be found in the AUTHORS file in the root of the source tree.
 import("../../build/webrtc.gni")
 
 group("utility") {
+  public_deps = [
+    ":audio_frame_operations",
+  ]
 }
+
+rtc_static_library("audio_frame_operations") {
+  sources = [
+    "audio_frame_operations.cc",
+    "audio_frame_operations.h",
+  ]
+
+  deps = [
+    "../..:webrtc_common",
+    "../../base:rtc_base_approved",
+    "../../modules/audio_coding:audio_format_conversion",
+  ]
+}