Disable ACTION_BOOT_COMPLETED event for 3rd party apps.

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 4c7315bcd75151acdd16cd3c955bcf0f98162ba3..f25a6e3d5d87aeb81273632601eb92e53834af96 100644
--- a/chrome/browser/about_flags.cc
+++ b/chrome/browser/about_flags.cc
@@ -33,6 +33,7 @@
 #include "chrome/common/features.h"
 #include "chrome/grit/chromium_strings.h"
 #include "chrome/grit/generated_resources.h"
+#include "components/arc/arc_features.h"
 #include "components/autofill/core/browser/autofill_experiments.h"
 #include "components/autofill/core/common/autofill_switches.h"
 #include "components/browser_sync/browser_sync_switches.h"
@@ -2102,6 +2103,12 @@ const FeatureEntry kFeatureEntries[] = {
     {"material-security-verbose", IDS_FLAGS_MATERIAL_SECURITY_VERBOSE_NAME,
      IDS_FLAGS_MATERIAL_SECURITY_VERBOSE_DESCRIPTION, kOsDesktop,
      MULTI_VALUE_TYPE(kSecurityVerboseChoices)},
+#if defined(OS_CHROMEOS)
+    {"arc-boot-completed-broadcast",
+     IDS_FLAGS_ARC_ACTION_BOOT_COMPLETED,
+     IDS_FLAGS_ARC_ACTION_BOOT_COMPLETED_DESCRIPTION, kOsCrOS,
+     FEATURE_VALUE_TYPE(features::kArcBootCompletedBroadcast)},
+#endif
     // NOTE: Adding new command-line switches requires adding corresponding
     // entries to enum "LoginCustomFlags" in histograms.xml. See note in
     // histograms.xml and don't forget to run AboutFlagsHistogramTest unit test.