Add flag for per-stream device selection for Android AAudio streams

Bug: 405950045
Change-Id: If94956dc778a7220a32fe543836ac7b7d5596a5e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6432252
Reviewed-by: Dale Curtis <dalecurtis@chromium.org>
Reviewed-by: Thomas Guilbert <tguilbert@chromium.org>
Commit-Queue: Maya Jelonkiewicz <mjel@google.com>
Cr-Commit-Position: refs/heads/main@{#1443978}

chrome/browser/about_flags.cc

@@ -11913,6 +11913,13 @@ const FeatureEntry kFeatureEntries[] = {
      FEATURE_VALUE_TYPE(input::features::kInputOnViz)},
 #endif  // BUILDFLAG(IS_ANDROID)
 
+#if BUILDFLAG(IS_ANDROID)
+    {"aaudio-per-stream-device-selection",
+     flag_descriptions::kAAudioPerStreamDeviceSelectionName,
+     flag_descriptions::kAAudioPerStreamDeviceSelectionDescription, kOsAndroid,
+     FEATURE_VALUE_TYPE(features::kAAudioPerStreamDeviceSelection)}
+#endif  // BUILDFLAG(IS_ANDROID)
+
     // Add new entries above this line.
 
     // NOTE: Adding a new flag requires adding a corresponding entry to enum

chrome/browser/flag-metadata.json

@@ -28,6 +28,11 @@
 //   flag-never-expire-list.json.
 
 [
+  {
+    "name": "aaudio-per-stream-device-selection",
+    "owners": [ "mjel@google.com", "cros-web-apps-team@google.com" ],
+    "expiry_milestone": 150
+  },
   {
     "name": "accessible-pdf-form",
     "owners": [ "bravi@microsoft.com", "mohitb@microsoft.com" ],

chrome/browser/flag_descriptions.cc

@@ -4296,6 +4296,12 @@ const char kRewriterAPIForGeminiNanoDescription[] =
 
 #if BUILDFLAG(IS_ANDROID)
 
+const char kAAudioPerStreamDeviceSelectionName[] =
+    "AAudio per-stream device selection";
+const char kAAudioPerStreamDeviceSelectionDescription[] =
+    "Enables per-stream device selection for AAudio streams. No effect on "
+    "versions of Android prior to Android Q.";
+
 const char kAccessibilityDeprecateTypeAnnounceName[] =
     "Accessibility Deprecate TYPE_ANNOUNCE";
 const char kAccessibilityDeprecateTypeAnnounceDescription[] =

chrome/browser/flag_descriptions.h

@@ -2518,6 +2518,9 @@ extern const char kRewriterAPIForGeminiNanoDescription[];
 
 #if BUILDFLAG(IS_ANDROID)
 
+extern const char kAAudioPerStreamDeviceSelectionName[];
+extern const char kAAudioPerStreamDeviceSelectionDescription[];
+
 extern const char kAccessibilityDeprecateTypeAnnounceName[];
 extern const char kAccessibilityDeprecateTypeAnnounceDescription[];
 extern const char kAccessibilityIncludeLongClickActionName[];

media/audio/audio_features.cc

@@ -37,6 +37,16 @@ BASE_FEATURE(kUseAAudioDriver,
 BASE_FEATURE(kUseAAudioInput,
              "UseAAudioInput",
              base::FEATURE_ENABLED_BY_DEFAULT);
+
+// Enables selection of audio devices for each individual AAudio stream instead
+// of using communication streams and managing the system-wide communication
+// route. This is not fully reliable on all Android devices.
+//
+// Requires `UseAAudioDriver`, `UseAAudioInput`, and an Android API level >=
+// `AAUDIO_MIN_API`, otherwise it will have no effect.
+BASE_FEATURE(kAAudioPerStreamDeviceSelection,
+             "AAudioPerStreamDeviceSelection",
+             base::FEATURE_DISABLED_BY_DEFAULT);
 #endif
 
 }  // namespace features

media/audio/audio_features.h

@@ -14,6 +14,7 @@ namespace features {
 #if BUILDFLAG(IS_ANDROID)
 MEDIA_EXPORT BASE_DECLARE_FEATURE(kUseAAudioDriver);
 MEDIA_EXPORT BASE_DECLARE_FEATURE(kUseAAudioInput);
+MEDIA_EXPORT BASE_DECLARE_FEATURE(kAAudioPerStreamDeviceSelection);
 #endif
 
 }  // namespace features

tools/metrics/histograms/enums.xml

@@ -12435,6 +12435,7 @@ from previous Chrome versions.
   <int value="-711890895" label="enable-website-settings-manager"/>
   <int value="-711422585" label="kSignInProfileCreationEnterprise:disabled"/>
   <int value="-710794209" label="PersonalizationJelly:enabled"/>
+  <int value="-710538344" label="AAudioPerStreamDeviceSelection:disabled"/>
   <int value="-709058455" label="ui-slow-animations"/>
   <int value="-708482536" label="Cormorant:disabled"/>
   <int value="-707548346" label="MediaAppLens:enabled"/>
@@ -15432,6 +15433,7 @@ from previous Chrome versions.
   <int value="448463569" label="NewShortcutMapping:disabled"/>
   <int value="449793694" label="OmniboxNumWebZpsRelatedSearches:disabled"/>
   <int value="450440544" label="ShowKiteForSupervisedUsers:enabled"/>
+  <int value="451132705" label="AAudioPerStreamDeviceSelection:enabled"/>
   <int value="451196246" label="disable-impl-side-painting"/>
   <int value="452139294" label="VrShellExperimentalRendering:enabled"/>
   <int value="452395990" label="EnablePixDetection:disabled"/>