assistant: add option to enable stereo audio input

Bug: b:120240333
Test: locally compile and run on device
Change-Id: Ica8be43ed03c26bbd92dca8ccce82a6560fa5427
Reviewed-on: https://chromium-review.googlesource.com/c/1356136
Reviewed-by: Elly Fong-Jones <[email protected]>
Reviewed-by: Tao Wu <[email protected]>
Commit-Queue: Xiaohui Chen <[email protected]>
Cr-Commit-Position: refs/heads/master@{#612724}
diff --git a/chrome/browser/flag_descriptions.h b/chrome/browser/flag_descriptions.h
index 38a93ff..a23c0f1 100644
--- a/chrome/browser/flag_descriptions.h
+++ b/chrome/browser/flag_descriptions.h
@@ -2018,6 +2018,9 @@
 extern const char kEnableGoogleAssistantDspName[];
 extern const char kEnableGoogleAssistantDspDescription[];
 
+extern const char kEnableGoogleAssistantStereoInputName[];
+extern const char kEnableGoogleAssistantStereoInputDescription[];
+
 extern const char kEnableHomeLauncherName[];
 extern const char kEnableHomeLauncherDescription[];