Replace gflags usages with rtc_base/flags in all targets based on test_main

webrtc/modules/audio_processing/test/py_quality_assessment/apm_quality_assessment_gencfgs.py

Index: webrtc/modules/audio_processing/test/py_quality_assessment/apm_quality_assessment_gencfgs.py
diff --git a/webrtc/modules/audio_processing/test/py_quality_assessment/apm_quality_assessment_gencfgs.py b/webrtc/modules/audio_processing/test/py_quality_assessment/apm_quality_assessment_gencfgs.py
index d2764b06d1df174dfce18fb8d674d1a6a383cd4d..338c38c1060d4c85a32ce110aafcc430221d3727 100755
--- a/webrtc/modules/audio_processing/test/py_quality_assessment/apm_quality_assessment_gencfgs.py
+++ b/webrtc/modules/audio_processing/test/py_quality_assessment/apm_quality_assessment_gencfgs.py
@@ -27,7 +27,7 @@ def _GenerateDefaultOverridden(config_override):
 
   The default settings are loaded via "-all_default".
   Check "src/webrtc/modules/audio_processing/test/audioproc_float.cc" and search
-  for "if (FLAGS_all_default) {".
+  for "if (FLAG_all_default) {".
 
   For instance, in 55eb6d621489730084927868fed195d3645a9ec9 the default is this:
   settings.use_aec = rtc::Optional<bool>(true);