Mac Video Capture: expose --enable-avfoundation as tristate in chrome://flags

chrome/browser/about_flags.cc

Index: chrome/browser/about_flags.cc
diff --git a/chrome/browser/about_flags.cc b/chrome/browser/about_flags.cc
index 6f2a3f18279c67608852de17cd6032dfd2ad8509..4273efb2d12c60285c9c54d94fc1979580b47788 100644
--- a/chrome/browser/about_flags.cc
+++ b/chrome/browser/about_flags.cc
@@ -489,6 +489,12 @@ const Experiment::Choice kEnableDropSyncCredentialChoices[] = {
     password_manager::switches::kDisableDropSyncCredential, "" },
 };
 
+const Experiment::Choice kEnableAVFoundationChoices[] = {
+  { IDS_GENERIC_EXPERIMENT_CHOICE_DEFAULT, "", "" },
+  { IDS_GENERIC_EXPERIMENT_CHOICE_ENABLED, switches::kEnableAVFoundation, ""},
+  { IDS_GENERIC_EXPERIMENT_CHOICE_DISABLED, switches::kForceQTKit, ""}
+};
+
 // RECORDING USER METRICS FOR FLAGS:
 // -----------------------------------------------------------------------------
 // The first line of the experiment is the internal name. If you'd like to
@@ -1214,7 +1220,7 @@ const Experiment kExperiments[] = {
     IDS_FLAGS_ENABLE_AVFOUNDATION_NAME,
     IDS_FLAGS_ENABLE_AVFOUNDATION_DESCRIPTION,
     kOsMac,
-    SINGLE_VALUE_TYPE(switches::kEnableAVFoundation)
+    MULTI_VALUE_TYPE(kEnableAVFoundationChoices)
   },
 #endif
   {