Fix accidental redeclaration.

Introduced here:
https://codereview.webrtc.org/1306863003/

and caught by the Android bots.

TBR=turaj@webrtc.org

Review URL: https://codereview.webrtc.org/1310653002 .

Cr-Commit-Position: refs/heads/master@{#9759}
diff --git a/webrtc/modules/audio_processing/test/audioproc_float.cc b/webrtc/modules/audio_processing/test/audioproc_float.cc
index 268702e..3cea5b9 100644
--- a/webrtc/modules/audio_processing/test/audioproc_float.cc
+++ b/webrtc/modules/audio_processing/test/audioproc_float.cc
@@ -172,10 +172,10 @@
   StreamConfig reverse_input_config = {};
   StreamConfig reverse_output_config = {};
   if (process_reverse) {
-    StreamConfig reverse_input_config = {in_rev_file->sample_rate(),
-                                         in_rev_file->num_channels()};
-    StreamConfig reverse_output_config = {out_rev_file->sample_rate(),
-                                          out_rev_file->num_channels()};
+    reverse_input_config = {in_rev_file->sample_rate(),
+                            in_rev_file->num_channels()};
+    reverse_output_config = {out_rev_file->sample_rate(),
+                             out_rev_file->num_channels()};
   }
   while (in_file.ReadSamples(in_interleaved.size(),
                              &in_interleaved[0]) == in_interleaved.size()) {