Refine the accessibility label of Clear Browsing Data flow.

ios/chrome/app/strings/ios_strings.grd

Index: ios/chrome/app/strings/ios_strings.grd
diff --git a/ios/chrome/app/strings/ios_strings.grd b/ios/chrome/app/strings/ios_strings.grd
index c5b55c31b1e3b09c257be948a3565aae2927d918..b4ea69b61102cd2a0274722f50d314d735693297 100644
--- a/ios/chrome/app/strings/ios_strings.grd
+++ b/ios/chrome/app/strings/ios_strings.grd
@@ -507,6 +507,9 @@ locale.  The strings in this file are specific to iOS.
       <message name="IDS_IOS_CLEAR_BUTTON" desc="Title for the button used to clear data. [Length: 20em] [iOS only]">
         Clear Browsing Data
       </message>
+      <message name="IDS_IOS_CONFIRM_CLEAR_BUTTON" desc="Accessibility label for the action sheet button used to clear data. [iOS only]">

[lindsayw, 2017/03/16 18:49:52]

nit:

Can we please include specifically "confirm" in the desc here? Along the lines
of "...for the action sheet button used to confirm clearing data." or something
akin to that?

[lpromero, 2017/03/17 13:34:11]

Good call. Done.

+        Confirm Clear Browsing Data
+      </message>
       <message name="IDS_IOS_CLEAR_CACHE" desc="Label for the option in settings to clear the cache. In titlecase. [Length: 20em] [iOS only]">
         Cached Images and Files
       </message>