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..6b85c1ad34e002fab764bf3ebf70400ac61f76eb 100644
--- a/components/search_engines/template_url_prepopulate_data.h
+++ b/components/search_engines/template_url_prepopulate_data.h
@@ -42,6 +42,13 @@ std::vector<std::unique_ptr<TemplateURLData>> GetPrepopulatedEngines(
     PrefService* prefs,
     size_t* default_search_provider_index);
 
+// Loads extra prepopulated engines for the given locale. If the engines are
+// already loaded, need_to-load will be set false.

[Peter Kasting, 2016/09/19 21:06:23]

Nit: How about this (I rewrote both functions' comments for parallelism, focus
on the second one):

// Returns the prepopulated URLs for the current country.
// |default_search_provider_index| is set to the index of the default search
// provider within the returned vector.
std::vector<std::unique_ptr<TemplateURLData>> GetPrepopulatedEngines(
    PrefService* prefs,
    size_t* default_search_provider_index);

// 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>>
GetPrepopulatedEnginesForNonDefaultLocale(const std::string& locale,
                                          PrefService* prefs);

This fixes these issues:
* Document the expected format of |locale|, since a "locale" can be many things.
* Document that this checks the current country and avoids doing anything if the
locale matches
* Avoid outparam entirely, since it's confusing, and callers can just check if
the returned vector is empty.

[Ian Wen, 2016/09/20 04:48:03]

Done.

+std::vector<std::unique_ptr<TemplateURLData>> GetLocalPrepopulatedEngines(

[Peter Kasting, 2016/09/19 21:06:23]

Should this function be #if'd for Android-only?  It seems like that's the only
place it's called.

[Ian Wen, 2016/09/20 04:48:03]

Done.

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