Concatenate string literals at compile time.

This CL was generated by running:
git ls-files | grep ".cc" | xargs perl -i -ne 'BEGIN {undef $/}; s/("[\s\n]*<<[\s\n]*")/" "/g; print;'; git cl format

After that I manually edited modules/audio_processing/gain_controller2.cc to preserve its original
formatting.

This primary benefit of this change is a small reduction in binary size.

Bug: None
Change-Id: I689fa7ba9c717c314bb167e5d592c3c4e0871e29
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/165961
Reviewed-by: Alessio Bazzica <alessiob@webrtc.org>
Reviewed-by: Karl Wiberg <kwiberg@webrtc.org>
Commit-Queue: Jonas Olsson <jonasolsson@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#30251}

modules/audio_coding/neteq/tools/neteq_input.cc

@@ -21,13 +21,24 @@ NetEqInput::PacketData::~PacketData() = default;
 std::string NetEqInput::PacketData::ToString() const {
   rtc::StringBuilder ss;
   ss << "{"
-     << "time_ms: " << static_cast<int64_t>(time_ms) << ", "
-     << "header: {"
-     << "pt: " << static_cast<int>(header.payloadType) << ", "
-     << "sn: " << header.sequenceNumber << ", "
-     << "ts: " << header.timestamp << ", "
-     << "ssrc: " << header.ssrc << "}, "
-     << "payload bytes: " << payload.size() << "}";
+        "time_ms: "
+     << static_cast<int64_t>(time_ms)
+     << ", "
+        "header: {"
+        "pt: "
+     << static_cast<int>(header.payloadType)
+     << ", "
+        "sn: "
+     << header.sequenceNumber
+     << ", "
+        "ts: "
+     << header.timestamp
+     << ", "
+        "ssrc: "
+     << header.ssrc
+     << "}, "
+        "payload bytes: "
+     << payload.size() << "}";
   return ss.Release();
 }