Increase Request Mobile Site character limit to 25em.

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 79d69d923d635ef2386ba4ca4c7279df387228a8..7e12be94c69b6a8c19fa82af6a57843298a43528 100644
--- a/ios/chrome/app/strings/ios_strings.grd
+++ b/ios/chrome/app/strings/ios_strings.grd
@@ -1453,7 +1453,7 @@ Your data was encrypted with your sync passphrase on <ph name="TIME">$2<ex>Sept
       <message name="IDS_IOS_TOOLS_MENU_REQUEST_DESKTOP_SITE" desc="The iOS menu item for requesting the desktop site [Length: 15em] [iOS only]">
         Request Desktop Site
       </message>
-      <message name="IDS_IOS_TOOLS_MENU_REQUEST_MOBILE_SITE" desc="The iOS menu item for requesting the mobile site [Length: 15em] [iOS only]">
+      <message name="IDS_IOS_TOOLS_MENU_REQUEST_MOBILE_SITE" desc="The iOS menu item for requesting the mobile site [Length: 25em] [iOS only]">

[Eugene But (OOO till 7-30), 2017/04/07 16:49:41]

Are there any existing tools items that have 25em limit? I'm worrying that 25
could make the menu very wide.

         Request Mobile Site
       </message>
       <message name="IDS_IOS_TOOLS_MENU_SETTINGS" desc="The iOS menu item for opening the settings [Length: 15em] [iOS only]">