[Signin iOS] Update title in merging data dialog

ios/chrome/app/strings/ios_google_chrome_strings.grd

Index: ios/chrome/app/strings/ios_google_chrome_strings.grd
diff --git a/ios/chrome/app/strings/ios_google_chrome_strings.grd b/ios/chrome/app/strings/ios_google_chrome_strings.grd
index 4acd83142b61e972157b2616a87a1cd236405d84..12aca122958b14c138048673c9f33f3af038deb6 100644
--- a/ios/chrome/app/strings/ios_google_chrome_strings.grd
+++ b/ios/chrome/app/strings/ios_google_chrome_strings.grd
@@ -210,6 +210,9 @@ locale.  The strings in this file are specific to iOS.
       <message name="IDS_IOS_OPTIONS_ENABLE_PHYSICAL_WEB_DETAILS" desc="The detailed description of an option to enable scanning for nearby devices broadcasting URLs.">
         Discover web pages sent by nearby objects. When Bluetooth is turned on, Chrome can gather web pages associated with objects around you and send them anonymously to Google to find the most useful ones. <ph name="BEGIN_LINK">BEGIN_LINK</ph>Learn more<ph name="END_LINK">END_LINK</ph>
       </message>
+      <message name="IDS_IOS_OPTIONS_IMPORT_DATA_TITLE_SIGNIN" desc="The title of the Import Data settings screen when signing in. [30em]">
+        Sign in to Chrome
+      </message>
       <message name="IDS_IOS_OPTIONS_PRIVACY_FOOTER" desc="Footer for the clear browsing data dialog [Length: 300em] [iOS only]">
         Google Chrome may use web services to improve your browsing experience. You may optionally disable these services. <ph name="BEGIN_LINK">BEGIN_LINK</ph>Learn more<ph name="END_LINK">END_LINK</ph>
       </message>