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chrome/browser/installable/installable_logging.h

Index: chrome/browser/installable/installable_logging.h
diff --git a/chrome/browser/installable/installable_logging.h b/chrome/browser/installable/installable_logging.h
index 766287abfed8629517c66fdd54904c7c2ccbc437..304a7068a9971cfc6b68785333531b2351d80f1c 100644
--- a/chrome/browser/installable/installable_logging.h
+++ b/chrome/browser/installable/installable_logging.h
@@ -13,10 +13,9 @@ class WebContents;
 
 // These values are a central reference for installability errors. The
 // InstallableManager will specify an InstallableErrorCode (or
-// NO_ERROR_DETECTED) in its result. Clients may also add their own error codes
-// to this list, and utilise LogErrorToConsole to write a message to the
-// devtools console.
-// TODO(dominickn) add an UMA metric for this enum.
+// NO_ERROR_DETECTED) in its result. Clients may also add their own error codes,
+// and utilise LogErrorToConsole to write a message to the devtools console.
+// This enum backs an UMA histogram, so it must be treated as append-only.
 enum InstallableErrorCode {

[benwells, 2016/08/11 04:47:34]

Nit: Maybe this type should be called something else, as not all of these are
errors.

   NO_ERROR_DETECTED,
   RENDERER_EXITING,
@@ -37,6 +36,14 @@ enum InstallableErrorCode {
   PLATFORM_NOT_SUPPORTED_ON_ANDROID,
   NO_ID_SPECIFIED,
   IDS_DO_NOT_MATCH,
+  ALREADY_INSTALLED,
+  INSUFFICIENT_ENGAGEMENT,
+  PACKAGE_NAME_OR_START_URL_EMPTY,
+  PREVIOUSLY_BLOCKED,
+  PREVIOUSLY_IGNORED,
+  SHOWING_NATIVE_APP_BANNER,
+  SHOWING_WEB_APP_BANNER,
+  FAILED_TO_CREATE_BANNER,
   MAX_ERROR_CODE,
 };