Add signin metrics access points used on iOS.

components/signin/core/browser/signin_metrics.h

Index: components/signin/core/browser/signin_metrics.h
diff --git a/components/signin/core/browser/signin_metrics.h b/components/signin/core/browser/signin_metrics.h
index a83851cf7f1c6a7b897c4b559fca975b41cee6c3..c771e122d8fc0397c77e46f8cd935b5eb6381201 100644
--- a/components/signin/core/browser/signin_metrics.h
+++ b/components/signin/core/browser/signin_metrics.h
@@ -139,6 +139,8 @@ enum class AccessPoint : int {
   ACCESS_POINT_UNKNOWN,  // This should never have been used to get signin URL.
   ACCESS_POINT_PASSWORD_BUBBLE,
   ACCESS_POINT_AUTOFILL_DROPDOWN,
+  ACCESS_POINT_RESIGN_IN_INFOBAR,

[Roger Tawa OOO till Jul 10th, 2016/08/17 17:20:22]

The separation with _ seems little off to me.  I'd suggested: xxx_RESIGNIN_xxx
or maybe xxx_RE_SIGNIN_xxx, mostly because" resign" is a real word with a
different meaning.

[bzanotti, 2016/08/18 08:45:24]

I was following the naming we've been using downstream, but this is a very good
point. Updated!

+  ACCESS_POINT_TAB_SWITCHER,
   ACCESS_POINT_MAX,  // This must be last.
 };