Translate: move UMA related code in TranslateManager to TranslateManagerMetrics

chrome/renderer/translate/translate_helper_metrics.h

Index: chrome/renderer/translate/translate_helper_metrics.h
diff --git a/chrome/renderer/translate/translate_helper_metrics.h b/chrome/renderer/translate/translate_helper_metrics.h
index 43c50fc4d5f9b524e5882e90f31a21ded2eb2e9d..af23d82336cdfe60ca0b7f7ee63b46111031e62b 100644
--- a/chrome/renderer/translate/translate_helper_metrics.h
+++ b/chrome/renderer/translate/translate_helper_metrics.h
@@ -12,8 +12,7 @@
 namespace TranslateHelperMetrics {
 
 // An indexing type to query each UMA entry name via GetMetricsName() function.
-// Note: The implementation of GetMetricsName() should be updated when a new
-// entry is added here.
+// Note: |kMetricsEntries| should be updated when a new entry is added here.
 enum MetricsNameIndex {
   UMA_LANGUAGE_DETECTION,
   UMA_CONTENT_LANGUAGE,