Add support for GCM subtypes to desktop Instance ID implementation

chrome/browser/services/gcm/gcm_product_util.cc

+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "chrome/browser/services/gcm/gcm_product_util.h"
+
+#include "base/strings/string_piece.h"
+#include "base/strings/string_util.h"
+#include "chrome/common/channel_info.h"
+#include "chrome/common/chrome_version.h"
+#include "chrome/common/pref_names.h"
+#include "components/pref_registry/pref_registry_syncable.h"
+#include "components/prefs/pref_service.h"
+#include "components/version_info/version_info.h"
+
+namespace gcm {
+
+namespace {
+
+std::string ToLowerAlphaNum(base::StringPiece in) {
+  std::string out;
+  out.reserve(in.size());
+  for (char ch : in) {
+    if (base::IsAsciiAlpha(ch) || base::IsAsciiDigit(ch))
+      out.push_back(base::ToLowerASCII(ch));
+  }
+  return out;
+}
+
+}  // namespace
+
+std::string GetProductCategoryForSubtypes(PrefService* prefs) {
+  std::string product_category_for_subtypes =
+      prefs->GetString(prefs::kGCMProductCategoryForSubtypes);
+  if (!product_category_for_subtypes.empty())
+    return product_category_for_subtypes;
+
+  std::string product = ToLowerAlphaNum(PRODUCT_SHORTNAME_STRING);
+  std::string ns = product == "chromium" ? "org" : "com";
+  std::string channel =
+      ToLowerAlphaNum(version_info::GetChannelString(chrome::GetChannel()));
+  std::string platform = ToLowerAlphaNum(version_info::GetOSType());
+  product_category_for_subtypes =
+      ns + '.' + product + '.' + channel + '.' + platform;
+
+  prefs->SetString(prefs::kGCMProductCategoryForSubtypes,
+                   product_category_for_subtypes);
+  return product_category_for_subtypes;
+}
+
+void RegisterProfilePrefs(user_prefs::PrefRegistrySyncable* registry) {
+  registry->RegisterStringPref(prefs::kGCMProductCategoryForSubtypes,
+                               std::string() /* default_value */);
+}
+
+}  // namespace gcm