Translate: adopt html lang attribute if valid value is provided

chrome/renderer/translate/translate_helper_metrics.cc

Index: chrome/renderer/translate/translate_helper_metrics.cc
diff --git a/chrome/renderer/translate/translate_helper_metrics.cc b/chrome/renderer/translate/translate_helper_metrics.cc
index 25bdf536f57bd82dafc1fc15418a2feaeb9fdc52..d58343829abaf82c9b1765ba802a8e50b97cf872 100644
--- a/chrome/renderer/translate/translate_helper_metrics.cc
+++ b/chrome/renderer/translate/translate_helper_metrics.cc
@@ -13,6 +13,7 @@ namespace {
 // a corresponding index in MetricsNameIndex and an entry in |kMetricsEntries|.
 const char kRenderer4LanguageDetection[] = "Renderer4.LanguageDetection";
 const char kTranslateContentLanguage[] = "Translate.ContentLanguage";
+const char kTranslateHtmlLang[] = "Translate.HtmlLang";
 const char kTranslateLanguageVerification[] = "Translate.LanguageVerification";
 const char kTranslateTimeToBeReady[] = "Translate.TimeToBeReady";
 const char kTranslateTimeToLoad[] = "Translate.TimeToLoad";
@@ -30,6 +31,8 @@ const MetricsEntry kMetricsEntries[] = {
     kRenderer4LanguageDetection },
   { TranslateHelperMetrics::UMA_CONTENT_LANGUAGE,
     kTranslateContentLanguage },
+  { TranslateHelperMetrics::UMA_HTML_LANG,
+    kTranslateHtmlLang },
   { TranslateHelperMetrics::UMA_LANGUAGE_VERIFICATION,
     kTranslateLanguageVerification },
   { TranslateHelperMetrics::UMA_TIME_TO_BE_READY,
@@ -45,25 +48,36 @@ const MetricsEntry kMetricsEntries[] = {
 COMPILE_ASSERT(arraysize(kMetricsEntries) == TranslateHelperMetrics::UMA_MAX,
                arraysize_of_kMetricsEntries_should_be_UMA_MAX);
 
+void ReportLanguageCheck(const char* metric_name,
+                         const std::string& provided_code,
+                         const std::string& revised_code) {
+  if (provided_code.empty()) {
+    UMA_HISTOGRAM_ENUMERATION(metric_name,

[Ilya Sherman, 2013/05/22 20:26:17]

This won't work as you want it to -- the histogram name that's passed to an
UMA_HISTOGRAM_ macro needs to be a runtime constant, as the macro defines a
static local variable.  I'd recommend defining a helper function that takes the
|provided_code| and |revised_code| and returns the metric (NOT_PROVIDED, VALID,
or INVALID) that should be logged; and invoking this helper function where you
are currently calling ReportLanguageCheck.

[Takashi Toyoshima, 2013/05/23 00:37:14]

Thanks.
As you said, unit_tests fails on this.
(Sorry, I should notice that before asking on review)
I'll follow your suggestion.

+                              TranslateHelperMetrics::LANGUAGE_NOT_PROVIDED,
+                              TranslateHelperMetrics::LANGUAGE_MAX);
+  } else if (provided_code == revised_code) {
+    UMA_HISTOGRAM_ENUMERATION(metric_name,
+                              TranslateHelperMetrics::LANGUAGE_VALID,
+                              TranslateHelperMetrics::LANGUAGE_MAX);
+  } else {
+    UMA_HISTOGRAM_ENUMERATION(metric_name,
+                              TranslateHelperMetrics::LANGUAGE_INVALID,
+                              TranslateHelperMetrics::LANGUAGE_MAX);
+  }
+}
+
 }  // namespace
 
 namespace TranslateHelperMetrics {
 
 void ReportContentLanguage(const std::string& provided_code,
                            const std::string& revised_code) {
-  if (provided_code.empty()) {
-    UMA_HISTOGRAM_ENUMERATION(kTranslateContentLanguage,
-                              CONTENT_LANGUAGE_NOT_PROVIDED,
-                              CONTENT_LANGUAGE_MAX);
-  } else if (provided_code == revised_code) {
-    UMA_HISTOGRAM_ENUMERATION(kTranslateContentLanguage,
-                              CONTENT_LANGUAGE_VALID,
-                              CONTENT_LANGUAGE_MAX);
-  } else {
-    UMA_HISTOGRAM_ENUMERATION(kTranslateContentLanguage,
-                              CONTENT_LANGUAGE_INVALID,
-                              CONTENT_LANGUAGE_MAX);
-  }
+  ReportLanguageCheck(kTranslateContentLanguage, provided_code, revised_code);
+}
+
+void ReportHtmlLang(const std::string& provided_code,
+                    const std::string& revised_code) {
+  ReportLanguageCheck(kTranslateHtmlLang, provided_code, revised_code);
 }
 
 void ReportLanguageVerification(LanguageVerificationType type) {