JsonSchemaCompiler: Remove redundant PopulateItem overloads.

PopulateItem is used when parsing arrays. We should never be parsing
arrays of optional types (which are represented as std::unique_ptr).
Remove these overloads.

BUG=None

Change-Id: Ia29ef89bd555cbfad10b92e9963e4fda431495a0
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2380322
Commit-Queue: Devlin <rdevlin.cronin@chromium.org>
Auto-Submit: Karan Bhatia <karandeepb@chromium.org>
Reviewed-by: Devlin <rdevlin.cronin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#802722}

tools/json_schema_compiler/util.h

@@ -39,19 +39,6 @@ bool PopulateItem(const base::Value& from,
                   base::string16* error);
 bool PopulateItem(const base::Value& from, std::unique_ptr<base::Value>* out);
 
-// This template is used for types generated by tools/json_schema_compiler.
-template <class T>
-bool PopulateItem(const base::Value& from, std::unique_ptr<T>* out) {
-  const base::DictionaryValue* dict = nullptr;
-  if (!from.GetAsDictionary(&dict))
-    return false;
-  std::unique_ptr<T> obj(new T());
-  if (!T::Populate(*dict, obj.get()))
-    return false;
-  *out = std::move(obj);
-  return true;
-}
-
 // This template is used for types generated by tools/json_schema_compiler.
 template <class T>
 bool PopulateItem(const base::Value& from, T* out) {
@@ -65,19 +52,6 @@ bool PopulateItem(const base::Value& from, T* out) {
   return true;
 }
 
-// This template is used for types generated by tools/json_schema_compiler with
-// error generation enabled.
-template <class T>
-bool PopulateItem(const base::Value& from,
-                  std::unique_ptr<T>* out,
-                  base::string16* error) {
-  std::unique_ptr<T> obj(new T());
-  if (!T::Populate(from, obj.get(), error))
-    return false;
-  *out = std::move(obj);
-  return true;
-}
-
 // This template is used for types generated by tools/json_schema_compiler with
 // error generation enabled.
 template <class T>