Move LanguageUsageMetrics and TranslateBrowserMetrics to components

LanguageUsageMetrics is moved to its own component because it is used
both in the translate component and directly in the browser.

TranslateBrowserMetrics is moved to the translate component.

BUG=331509
TBR=jochen

Review URL: https://codereview.chromium.org/131203002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@243946 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 53 insertions, 0 deletions

diff --git a/components/language_usage_metrics/language_usage_metrics.h b/components/language_usage_metrics/language_usage_metrics.h
new file mode 100644
index 0000000..ffde58b
--- /dev/null
+++ b/components/language_usage_metrics/language_usage_metrics.h
@@ -0,0 +1,53 @@
+// Copyright 2014 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.
+
+#ifndef COMPONENTS_LANGUAGE_USAGE_METRICS_LANGUAGE_USAGE_METRICS_H_
+#define COMPONENTS_LANGUAGE_USAGE_METRICS_LANGUAGE_USAGE_METRICS_H_
+
+#include <set>
+#include <string>
+
+#include "base/basictypes.h"
+#include "base/gtest_prod_util.h"
+
+namespace language_usage_metrics {
+
+// Methods to record language usage as UMA histograms.
+class LanguageUsageMetrics {
+ public:
+  // Records accept languages as a UMA histogram. |accept_languages| is a
+  // case-insensitive comma-separated list of languages/locales of either xx,
+  // xx-YY, or xx_YY format where xx is iso-639 language code and YY is iso-3166
+  // country code. Country code is ignored. That is, xx and XX-YY are considered
+  // identical and recorded once.
+  static void RecordAcceptLanguages(const std::string& accept_languages);
+
+  // Records the application language as a UMA histogram. |application_locale|
+  // is a case-insensitive locale string of either xx, xx-YY, or xx_YY format.
+  // Only the language part (xx in the example) is considered.
+  static void RecordApplicationLanguage(const std::string& application_locale);
+
+  // Parses |locale| and returns the language code. Returns 0 in case of errors.
+  // The language code is calculated from two alphabets. For example, if
+  // |locale| is 'en' which represents 'English', the codes of 'e' and 'n' are
+  // 101 and 110 respectively, and the language code will be 101 * 256 + 100 =
+  // 25966.
+  // |locale| should consist of only lower-case letters. This function doesn't
+  // check whether |locale| is valid locale or not strictly.
+  static int ToLanguageCode(const std::string &locale);
+
+ private:
+  DISALLOW_IMPLICIT_CONSTRUCTORS(LanguageUsageMetrics);
+
+  // Parses |accept_languages| and returns a set of language codes in
+  // |languages|.
+  static void ParseAcceptLanguages(const std::string& accept_languages,
+                                   std::set<int>* languages);
+
+  FRIEND_TEST_ALL_PREFIXES(LanguageUsageMetricsTest, ParseAcceptLanguages);
+};
+
+}  // namespace language_usage_metrics
+
+#endif  // COMPONENTS_LANGUAGE_USAGE_METRICS_LANGUAGE_USAGE_METRICS_H_