[Clean-up] Remove some dead code for handling Webstore sign-in.

BUG=388083
TEST=code still compiles
[email protected]
NOPRESUBMIT=true
NOTRY=true

Review URL: https://codereview.chromium.org/579033002

Cr-Commit-Position: refs/heads/master@{#296884}
diff --git a/extensions/browser/extension_function_histogram_value.h b/extensions/browser/extension_function_histogram_value.h
index 28e3c75..ee7491f 100644
--- a/extensions/browser/extension_function_histogram_value.h
+++ b/extensions/browser/extension_function_histogram_value.h
@@ -806,7 +806,7 @@
   BLUETOOTHSOCKET_SEND,
   BLUETOOTHSOCKET_GETINFO,
   BLUETOOTHSOCKET_GETSOCKETS,
-  WEBSTOREPRIVATE_SIGNINFUNCTION,
+  DELETED_WEBSTOREPRIVATE_SIGNINFUNCTION,
   DELETED_SHELL_CREATEWINDOW,
   FILESYSTEMPROVIDERINTERNAL_GETMETADATAREQUESTEDSUCCESS,
   DELETED_FILESYSTEMPROVIDERINTERNAL_GETMETADATAREQUESTEDERROR,