Use std::make_unique instead of absl::make_unique.

WebRTC is now using C++14 so there is no need to use the Abseil version
of std::make_unique.

This CL has been created with the following steps:

git grep -l absl::make_unique | sort | uniq > /tmp/make_unique.txt
git grep -l absl::WrapUnique | sort | uniq > /tmp/wrap_unique.txt
git grep -l "#include <memory>" | sort | uniq > /tmp/memory.txt

diff --new-line-format="" --unchanged-line-format="" \
  /tmp/make_unique.txt /tmp/wrap_unique.txt | sort | \
  uniq > /tmp/only_make_unique.txt
diff --new-line-format="" --unchanged-line-format="" \
  /tmp/only_make_unique.txt /tmp/memory.txt | \
  xargs grep -l "absl/memory" > /tmp/add-memory.txt

git grep -l "\babsl::make_unique\b" | \
  xargs sed -i "s/\babsl::make_unique\b/std::make_unique/g"

git checkout PRESUBMIT.py abseil-in-webrtc.md

cat /tmp/add-memory.txt | \
  xargs sed -i \
  's/#include "absl\/memory\/memory.h"/#include <memory>/g'
git cl format
# Manual fix order of the new inserted #include <memory>

cat /tmp/only_make_unique | xargs grep -l "#include <memory>" | \
  xargs sed -i '/#include "absl\/memory\/memory.h"/d'

git ls-files | grep BUILD.gn | \
  xargs sed -i '/\/\/third_party\/abseil-cpp\/absl\/memory/d'

python tools_webrtc/gn_check_autofix.py \
  -m tryserver.webrtc -b linux_rel

# Repead the gn_check_autofix step for other platforms

git ls-files | grep BUILD.gn | \
  xargs sed -i 's/absl\/memory:memory/absl\/memory/g'
git cl format

Bug: webrtc:10945
Change-Id: I3fe28ea80f4dd3ba3cf28effd151d5e1f19aff89
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/153221
Commit-Queue: Mirko Bonadei <mbonadei@webrtc.org>
Reviewed-by: Alessio Bazzica <alessiob@webrtc.org>
Reviewed-by: Karl Wiberg <kwiberg@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#29209}
diff --git a/modules/audio_coding/neteq/neteq_impl_unittest.cc b/modules/audio_coding/neteq/neteq_impl_unittest.cc
index ded54bf..39c4e52 100644
--- a/modules/audio_coding/neteq/neteq_impl_unittest.cc
+++ b/modules/audio_coding/neteq/neteq_impl_unittest.cc
@@ -14,7 +14,6 @@
 #include <utility>
 #include <vector>
 
-#include "absl/memory/memory.h"
 #include "api/audio_codecs/builtin_audio_decoder_factory.h"
 #include "modules/audio_coding/neteq/accelerate.h"
 #include "modules/audio_coding/neteq/expand.h"
@@ -109,7 +108,7 @@
           config_.max_packets_in_buffer, config_.min_delay_ms, 1020054733,
           DelayManager::HistogramMode::INTER_ARRIVAL_TIME,
           config_.enable_rtx_handling, delay_peak_detector_, tick_timer_,
-          deps.stats.get(), absl::make_unique<Histogram>(50, 32745)));
+          deps.stats.get(), std::make_unique<Histogram>(50, 32745)));
       mock_delay_manager_ = mock.get();
       deps.delay_manager = std::move(mock);
     }
@@ -1567,7 +1566,7 @@
         new rtc::RefCountedObject<test::FunctionAudioDecoderFactory>(
             [sampling_freq, speech_type]() {
               std::unique_ptr<AudioDecoder> decoder =
-                  absl::make_unique<Decoder120ms>(sampling_freq, speech_type);
+                  std::make_unique<Decoder120ms>(sampling_freq, speech_type);
               RTC_CHECK_EQ(2, decoder->Channels());
               return decoder;
             });