Added histogram on successful check. Safe verification

chrome/browser/protector/histograms.h

Index: chrome/browser/protector/histograms.h
diff --git a/chrome/browser/protector/histograms.h b/chrome/browser/protector/histograms.h
index 71b5e68405ed8c1a472be19611b3c60d7a7c5e83..e00b814d17f57fd5167c83eb4b792a127259c6a3 100644
--- a/chrome/browser/protector/histograms.h
+++ b/chrome/browser/protector/histograms.h
@@ -12,10 +12,15 @@ namespace protector {
 // provider.
 extern const char kProtectorHistogramDefaultSearchProvider[];
 
+extern const char kProtectorBackupInvalidCounter[];
+extern const char kProtectorValueChangedCounter[];
+extern const char kProtectorValueValidCounter[];
+
 // Protector histogram values.
 enum ProtectorError {
   kProtectorErrorBackupInvalid,
   kProtectorErrorValueChanged,
+  kProtectorErrorValueValid,
 
   // This is for convenience only, must always be the last.
   kProtectorErrorCount