Add histograms to entire MergeSession flow.

google_apis/gaia/ubertoken_fetcher.cc

 // 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.
 
 #include "google_apis/gaia/ubertoken_fetcher.h"
 
 #include <vector>
 
 #include "base/logging.h"
+#include "base/metrics/histogram_macros.h"
 #include "base/rand_util.h"
 #include "base/time/time.h"
 #include "google_apis/gaia/gaia_auth_fetcher.h"
 #include "google_apis/gaia/gaia_constants.h"
 #include "google_apis/gaia/google_service_auth_error.h"
 #include "google_apis/gaia/oauth2_token_service.h"
 
 const int UbertokenFetcher::kMaxRetries = 3;
 
 UbertokenFetcher::UbertokenFetcher(
@@ skipping 31 matching lines @@
     const GoogleServiceAuthError& error) {
   // Retry only transient errors.
   bool should_retry =
       error.state() == GoogleServiceAuthError::CONNECTION_FAILED ||
       error.state() == GoogleServiceAuthError::SERVICE_UNAVAILABLE;
   if (should_retry) {
     if (retry_number_ < kMaxRetries) {
       // Calculate an exponential backoff with randomness of less than 1 sec.
       double backoff = base::RandDouble() + (1 << retry_number_);
       ++retry_number_;
+      UMA_HISTOGRAM_ENUMERATION("Signin.UberTokenRetry",
+          error.state(), GoogleServiceAuthError::NUM_STATES);
       retry_timer_.Stop();
       retry_timer_.Start(FROM_HERE,
                          base::TimeDelta::FromSecondsD(backoff),
                          this,
                          &UbertokenFetcher::ExchangeTokens);
       return;
     }
   } else {
     // The access token is invalid.  Tell the token service.
     OAuth2TokenService::ScopeSet scopes;
     scopes.insert(GaiaConstants::kOAuth1LoginScope);
     token_service_->InvalidateToken(account_id_, scopes, access_token_);
 
     // In case the access was just stale, try one more time.
     if (!second_access_token_request_) {
       second_access_token_request_ = true;
       RequestAccessToken();
       return;
     }
   }
 
+  UMA_HISTOGRAM_ENUMERATION("Signin.UberTokenFailure",
+      error.state(), GoogleServiceAuthError::NUM_STATES);
   consumer_->OnUbertokenFailure(error);
 }
 
 void UbertokenFetcher::OnGetTokenSuccess(
     const OAuth2TokenService::Request* request,
     const std::string& access_token,
     const base::Time& expiration_time) {
   DCHECK(!access_token.empty());
   access_token_ = access_token;
   access_token_request_.reset();
@@ skipping 17 matching lines @@
   access_token_request_ =
       token_service_->StartRequest(account_id_, scopes, this);
 }
 
 void UbertokenFetcher::ExchangeTokens() {
   gaia_auth_fetcher_.reset(new GaiaAuthFetcher(this,
                                                source_,
                                                request_context_));
   gaia_auth_fetcher_->StartTokenFetchForUberAuthExchange(access_token_);
 }