Add gtest as a dependency for neteq_quality_test_support.

webrtc/modules/audio_coding/BUILD.gn

 # Copyright (c) 2014 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")
 import("audio_coding.gni")
@@ skipping 1163 matching lines @@
     public_configs = [ "../..:common_inherited_config" ]
 
     if (is_clang) {
       # Suppress warnings from the Chromium Clang plugins (bugs.webrtc.org/163).
       configs -= [ "//build/config/clang:find_bad_constructs" ]
     }
 
     deps = [
       ":neteq",
       ":neteq_unittest_tools",
+      "//testing/gtest",
       "//third_party/gflags",
     ]
   }
 
   config("neteq_unittest_tools_config") {
     include_dirs = [ "tools" ]
   }
 
   source_set("neteq_unittest_tools") {
     testonly = true
@@ skipping 338 matching lines @@
     ]
 
     if (is_win) {
       cflags = [
         # Disable warnings to enable Win64 build, issue 1323.
         "/wd4267",  # size_t to int truncation
       ]
     }
   }
 }