Enable Chrome to tweak search engines for some locales

components/search_engines/template_url_prepopulate_data.h

Index: components/search_engines/template_url_prepopulate_data.h
diff --git a/components/search_engines/template_url_prepopulate_data.h b/components/search_engines/template_url_prepopulate_data.h
index 210a0f50f2345bf1ed88a0cf0d58767176ff8ff5..956814972873b8487eb74799954c8ad1687b71a9 100644
--- a/components/search_engines/template_url_prepopulate_data.h
+++ b/components/search_engines/template_url_prepopulate_data.h
@@ -35,13 +35,22 @@ void RegisterProfilePrefs(user_prefs::PrefRegistrySyncable* registry);
 // file then it returns the version specified there.
 int GetDataVersion(PrefService* prefs);
 
-// Loads the set of TemplateURLs from the prepopulate data. On return,
+// Returns the prepopulated URLs for the current country.
 // |default_search_provider_index| is set to the index of the default search
-// provider.
+// provider within the returned vector.
 std::vector<std::unique_ptr<TemplateURLData>> GetPrepopulatedEngines(
     PrefService* prefs,
     size_t* default_search_provider_index);
 
+#if defined(OS_ANDROID)
+// Returns the prepopulated URLs associated with |locale|, if it differs from
+// the current country.  |locale| should be a two-character uppercase ISO 3166-1
+// country code.
+std::vector<std::unique_ptr<TemplateURLData>> GetLocalPrepopulatedEngines(

[Peter Kasting, 2016/09/21 21:45:08]

Nit: The only thing I worry about with this function name is that I don't know
whether it's sufficiently obvious that, if the locale is the same as the current
one, this returns an empty vector.  The function name kinda sounds like it just
gets the engines for a particular locale.

However, the comment does say this, and my suggested name was pretty awkward. 
So maybe this is good enough.  I don't know.

[Ian Wen, 2016/09/21 23:12:38]

I added a clarification to make it more clear that vector should be empty if
locale is already loaded.

+    const std::string& locale,
+    PrefService* prefs);
+#endif
+
 // Returns all prepopulated engines for all locales. Used only by tests.
 std::vector<const PrepopulatedEngine*> GetAllPrepopulatedEngines();