Add feature flag for Conch GenAI features

Add flag and entry in chrome://flags to control Conch GenAI features.
Note that this flag won't have effect if the odml service is not
supported on the device, e.g. non-CBX.

This flag is only available in Ash Chrome.

Bug: b:350031897
Test: manually - See the flag in chrome://flags
Test: out/release/unit_tests --gtest_filter='AboutFlags*'
Change-Id: I08ccf35c19da529b051547d66e98207110ab27c0
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5968701
Reviewed-by: Pi-Hsun Shih <pihsun@chromium.org>
Commit-Queue: Jennifer Ling <hsuanling@google.com>
Cr-Commit-Position: refs/heads/main@{#1374508}

ash/constants/ash_features.cc

@@ -446,6 +446,9 @@ BASE_FEATURE(kConchExpandTranscriptionLanguage,
              "ConchExpandTranscriptionLanguage",
              base::FEATURE_DISABLED_BY_DEFAULT);
 
+// If enabled, conch will provide available GenAI features.
+BASE_FEATURE(kConchGenAi, "ConchGenAi", base::FEATURE_DISABLED_BY_DEFAULT);
+
 // If enabled, conch will use microphone to capture system audio.
 BASE_FEATURE(kConchSystemAudioFromMic,
              "ConchSystemAudioFromMic",

ash/constants/ash_features.h

@@ -138,6 +138,7 @@ BASE_DECLARE_FEATURE(kClipboardHistoryUrlTitles);
 COMPONENT_EXPORT(ASH_CONSTANTS) BASE_DECLARE_FEATURE(kConch);
 COMPONENT_EXPORT(ASH_CONSTANTS)
 BASE_DECLARE_FEATURE(kConchExpandTranscriptionLanguage);
+COMPONENT_EXPORT(ASH_CONSTANTS) BASE_DECLARE_FEATURE(kConchGenAi);
 COMPONENT_EXPORT(ASH_CONSTANTS) BASE_DECLARE_FEATURE(kConchSystemAudioFromMic);
 COMPONENT_EXPORT(ASH_CONSTANTS)
 BASE_DECLARE_FEATURE(kConsumerAutoUpdateToggleAllowed);

chrome/browser/about_flags.cc

@@ -11102,6 +11102,10 @@ const FeatureEntry kFeatureEntries[] = {
      flag_descriptions::kConchExpandTranscriptionLanguageName,
      flag_descriptions::kConchExpandTranscriptionLanguageDescription, kOsCrOS,
      FEATURE_VALUE_TYPE(ash::features::kConchExpandTranscriptionLanguage)},
+
+    {"conch-gen-ai", flag_descriptions::kConchGenAiName,
+     flag_descriptions::kConchGenAiDescription, kOsCrOS,
+     FEATURE_VALUE_TYPE(ash::features::kConchGenAi)},
 #endif  // BUILDFLAG(IS_CHROMEOS_ASH)
 
 #if BUILDFLAG(IS_ANDROID)

chrome/browser/flag-metadata.json

@@ -1595,6 +1595,11 @@
     "owners": ["hsuanling@google.com"],
     "expiry_milestone": 140
   },
+  {
+    "name": "conch-gen-ai",
+    "owners": ["hsuanling@google.com"],
+    "expiry_milestone": 140
+  },
   {
     "name": "conch-system-audio-from-mic",
     "owners": ["hsuanling@google.com"],

chrome/browser/flag_descriptions.cc

@@ -6335,6 +6335,10 @@ const char kConchExpandTranscriptionLanguageName[] =
 const char kConchExpandTranscriptionLanguageDescription[] =
     "Expand transcription language options for Conch on ChromeOS.";
 
+const char kConchGenAiName[] = "GenAI features for Conch";
+const char kConchGenAiDescription[] =
+    "Enable this flag to use GenAI for Conch on ChromeOS.";
+
 const char kConchSystemAudioFromMicName[] = "System audio capture for Conch";
 const char kConchSystemAudioFromMicDescription[] =
     "Capture system audio from microphone for Conch on ChromeOS.";

chrome/browser/flag_descriptions.h

@@ -3645,6 +3645,9 @@ extern const char kConchDescription[];
 extern const char kConchExpandTranscriptionLanguageName[];
 extern const char kConchExpandTranscriptionLanguageDescription[];
 
+extern const char kConchGenAiName[];
+extern const char kConchGenAiDescription[];
+
 extern const char kConchSystemAudioFromMicName[];
 extern const char kConchSystemAudioFromMicDescription[];
 

tools/metrics/histograms/enums.xml

@@ -18868,6 +18868,7 @@ from previous Chrome versions.
   <int value="-512151470" label="WebRtcPipeWireCamera:disabled"/>
   <int value="-511218457" label="NavBarColorMatchesTabBackground:enabled"/>
   <int value="-510488450" label="disable-pnacl"/>
+  <int value="-510428936" label="ConchGenAi:enabled"/>
   <int value="-510423102" label="ProductSpecificationsSync:enabled"/>
   <int value="-508488651" label="WebviewAccelerateSmallCanvases:enabled"/>
   <int value="-508346329" label="TerminalSystemAppLegacySettings:disabled"/>
@@ -22081,6 +22082,7 @@ from previous Chrome versions.
   <int value="797344274" label="OmniboxTriggerForPrerender2:disabled"/>
   <int value="797924041" label="DeferredShaping:enabled"/>
   <int value="798414711" label="BorealisForceDoubleScale:enabled"/>
+  <int value="798456441" label="ConchGenAi:disabled"/>
   <int value="798696013" label="ImeInputLogicMozc:enabled"/>
   <int value="798803191" label="ShareToGoogleCollections:disabled"/>
   <int value="799680074" label="ContextualSearchTranslationModel:enabled"/>