Revert "Prefix flag macros with WEBRTC_."

This reverts commit 5ccdc1331fcc3cd78eaa14408fe0c38d37a5a51d.

Reason for revert: Breaks downstream project.

Original change's description:
> Prefix flag macros with WEBRTC_.
> 
> Macros defined in rtc_base/flags.h are intended to be used to define
> flags in WebRTC's binaries (e.g. tests).
> 
> They are currently not prefixed and this could cause problems with
> downstream clients since these names are quite common.
> 
> This CL adds the 'WEBRTC_' prefix to them.
> 
> Generated with:
> 
> for x in DECLARE DEFINE; do
>   for y in bool int float string FLAG; do
>     git grep -l "\b$x\_$y\b" | \
>     xargs sed -i "s/\b$x\_$y\b/WEBRTC_$x\_$y/g"
>   done
> done
> git cl format
> 
> Bug: webrtc:9884
> Change-Id: I7b524762b6a3e5aa5b2fc2395edd3e1a0fe72591
> Reviewed-on: https://webrtc-review.googlesource.com/c/106682
> Reviewed-by: Karl Wiberg <kwiberg@webrtc.org>
> Commit-Queue: Mirko Bonadei <mbonadei@webrtc.org>
> Cr-Commit-Position: refs/heads/master@{#25270}

TBR=mbonadei@webrtc.org,kwiberg@webrtc.org

Change-Id: Ia79cd6066ecfd1511c34f1b30fd423e560ed6854
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: webrtc:9884
Reviewed-on: https://webrtc-review.googlesource.com/c/107160
Reviewed-by: Mirko Bonadei <mbonadei@webrtc.org>
Commit-Queue: Mirko Bonadei <mbonadei@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#25276}
diff --git a/modules/audio_coding/neteq/tools/rtp_encode.cc b/modules/audio_coding/neteq/tools/rtp_encode.cc
index f48b04d..5065ca1 100644
--- a/modules/audio_coding/neteq/tools/rtp_encode.cc
+++ b/modules/audio_coding/neteq/tools/rtp_encode.cc
@@ -40,24 +40,20 @@
 namespace {
 
 // Define command line flags.
-WEBRTC_DEFINE_bool(list_codecs, false, "Enumerate all codecs");
-WEBRTC_DEFINE_string(codec, "opus", "Codec to use");
-WEBRTC_DEFINE_int(frame_len,
-                  0,
-                  "Frame length in ms; 0 indicates codec default value");
-WEBRTC_DEFINE_int(bitrate,
-                  0,
-                  "Bitrate in kbps; 0 indicates codec default value");
-WEBRTC_DEFINE_int(payload_type,
-                  -1,
-                  "RTP payload type; -1 indicates codec default value");
-WEBRTC_DEFINE_int(cng_payload_type,
-                  -1,
-                  "RTP payload type for CNG; -1 indicates default value");
-WEBRTC_DEFINE_int(ssrc, 0, "SSRC to write to the RTP header");
-WEBRTC_DEFINE_bool(dtx, false, "Use DTX/CNG");
-WEBRTC_DEFINE_int(sample_rate, 48000, "Sample rate of the input file");
-WEBRTC_DEFINE_bool(help, false, "Print this message");
+DEFINE_bool(list_codecs, false, "Enumerate all codecs");
+DEFINE_string(codec, "opus", "Codec to use");
+DEFINE_int(frame_len, 0, "Frame length in ms; 0 indicates codec default value");
+DEFINE_int(bitrate, 0, "Bitrate in kbps; 0 indicates codec default value");
+DEFINE_int(payload_type,
+           -1,
+           "RTP payload type; -1 indicates codec default value");
+DEFINE_int(cng_payload_type,
+           -1,
+           "RTP payload type for CNG; -1 indicates default value");
+DEFINE_int(ssrc, 0, "SSRC to write to the RTP header");
+DEFINE_bool(dtx, false, "Use DTX/CNG");
+DEFINE_int(sample_rate, 48000, "Sample rate of the input file");
+DEFINE_bool(help, false, "Print this message");
 
 // Add new codecs here, and to the map below.
 enum class CodecType {