Do not FireRefreshTokenAvailable on empty robot account

This CL enforces the constraint that the account_id is not empty in
OAuth2TokenServiceDelegate FireRefreshTokenAvailable,
FireRefreshTokenRevoked and FireAuthErrorChanged. This is in the
interest of adding this semantic constraint to the oauth2_token_service
APIs which is already respected by most callsites.

There is one case that failed on ChromeOS tests (impacting multiple
tests, see first patchset here), in
DeviceOAuth2TokenServiceDelegate::DidGetSystemSalt, where the Robot
account Id might be empty. This is changed to call
FireRefreshTokenAvailable only if the robot account is set.


Bug: 960281
Change-Id: I8cc55cdc0f4c9c15c004c7fb20ed9e221ca1030b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1619811Reviewed-by: Xiyuan Xia <xiyuan@chromium.org>
Reviewed-by: Boris Sazonov <bsazonov@chromium.org>
Commit-Queue: Xiyuan Xia <xiyuan@chromium.org>
Auto-Submit: Pâris Meuleman <pmeuleman@chromium.org>
Cr-Commit-Position: refs/heads/master@{#664989}

chrome/browser/chromeos/settings/device_oauth2_token_service_delegate.cc

@@ -214,7 +214,9 @@ void DeviceOAuth2TokenServiceDelegate::DidGetSystemSalt(
     StartValidation();
 
   // Announce the token.
-  FireRefreshTokenAvailable(GetRobotAccountId());
+  if (!GetRobotAccountId().empty()) {
+    FireRefreshTokenAvailable(GetRobotAccountId());
+  }
   FireRefreshTokensLoaded();
 }
 

google_apis/gaia/oauth2_token_service_delegate.cc

@@ -71,12 +71,14 @@ void OAuth2TokenServiceDelegate::EndBatchChanges() {
 
 void OAuth2TokenServiceDelegate::FireRefreshTokenAvailable(
     const std::string& account_id) {
+  DCHECK(!account_id.empty());
   for (auto& observer : observer_list_)
     observer.OnRefreshTokenAvailable(account_id);
 }
 
 void OAuth2TokenServiceDelegate::FireRefreshTokenRevoked(
     const std::string& account_id) {
+  DCHECK(!account_id.empty());
   for (auto& observer : observer_list_)
     observer.OnRefreshTokenRevoked(account_id);
 }
@@ -89,6 +91,7 @@ void OAuth2TokenServiceDelegate::FireRefreshTokensLoaded() {
 void OAuth2TokenServiceDelegate::FireAuthErrorChanged(
     const std::string& account_id,
     const GoogleServiceAuthError& error) {
+  DCHECK(!account_id.empty());
   for (auto& observer : observer_list_)
     observer.OnAuthErrorChanged(account_id, error);
 }