Pass time since profile was loaded and request count on each ListAccount request to Gaia.

google_apis/gaia/gaia_auth_fetcher.cc

Index: google_apis/gaia/gaia_auth_fetcher.cc
diff --git a/google_apis/gaia/gaia_auth_fetcher.cc b/google_apis/gaia/gaia_auth_fetcher.cc
index 789fa4744d472219cd7c4553d9efb5bfbd6e3a10..59c0f653ce2683dc6cd2677d6e0be9b714a6a7fd 100644
--- a/google_apis/gaia/gaia_auth_fetcher.cc
+++ b/google_apis/gaia/gaia_auth_fetcher.cc
@@ -649,12 +649,19 @@ void GaiaAuthFetcher::StartOAuthLogin(const std::string& access_token,
                             oauth_login_gurl_, net::LOAD_NORMAL);
 }
 
-void GaiaAuthFetcher::StartListAccounts() {
+void GaiaAuthFetcher::StartListAccounts(const base::Time& profile_load_time) {
   DCHECK(!fetch_pending_) << "Tried to fetch two things at once!";
 
+  // Report the time since the profile was loaded and the number of this request
+  // in order to debug channel ID issues observed on Gaia.
+  static int32_t list_accounts_request_counter = 0;
+  std::string extra_headers = base::StringPrintf(
+      "Origin: %s \r\n RequestCount: %d \r\n TimeSinceProfileLoad: %ld",
+      "https://www.google.com", list_accounts_request_counter++,
+      (base::Time::Now() - profile_load_time).InMilliseconds());
   CreateAndStartGaiaFetcher(" ",  // To force an HTTP POST.
-                            "Origin: https://www.google.com",
-                            list_accounts_gurl_, net::LOAD_NORMAL);
+                            extra_headers, list_accounts_gurl_,

[vanupam, 2017/02/15 03:08:28]

list_accounts_gurl_ is assigned in the constructor via
ListAccountsURLWithSource(source) which lets a source=xxx url param be set.

Since this is a debugging-only change (hopefully, it will be reverted in the
near term), instead of adding new headers (which will require server side
changes to propagate into debug logs) can we append e.g. _counter_loadtime to
the source param; (The source param value has no semantics in Gaia.)

[msarda, 2017/03/01 10:26:36]

Done.

+                            net::LOAD_NORMAL);
 }
 
 void GaiaAuthFetcher::StartLogOut() {