Return a transient error if chrome hasn't loaded its refresh tokens.

The identity service fails fast if chrome's refresh tokens are not yet
loaded. However, it does not distinguish between a transient failure due
to the refresh tokens not having loaded yet and a persistent failure due
to not having a refresh token for the requested account. Avoid this by
returning transient errors until the refresh tokens are loaded.

Bug: 855002
Change-Id: I4cfa1d52987a3ed9fbec9a8600c87c535b9e0252
Reviewed-on: https://chromium-review.googlesource.com/1113086Reviewed-by: Stuart Langley <slangley@chromium.org>
Commit-Queue: Sam McNally <sammc@chromium.org>
Cr-Commit-Position: refs/heads/master@{#570294}

chrome/browser/chromeos/drive/drive_integration_service.cc

@@ -259,6 +259,7 @@ class DriveIntegrationService::DriveFsHolder
   void OnMounted(const base::FilePath& path) override;
   std::unique_ptr<drivefs::DriveFsHost::MojoConnectionDelegate>
   CreateMojoConnectionDelegate() override;
+  bool AreRefreshTokensReady() override;
 
   Profile* const profile_;
 
@@ -307,6 +308,14 @@ DriveIntegrationService::DriveFsHolder::CreateMojoConnectionDelegate() {
   return Delegate::CreateMojoConnectionDelegate();
 }
 
+bool DriveIntegrationService::DriveFsHolder::AreRefreshTokensReady() {
+  const auto state = ProfileOAuth2TokenServiceFactory::GetForProfile(profile_)
+                         ->GetDelegate()
+                         ->GetLoadCredentialsState();
+  return state != OAuth2TokenServiceDelegate::LOAD_CREDENTIALS_IN_PROGRESS &&
+         state != OAuth2TokenServiceDelegate::LOAD_CREDENTIALS_NOT_STARTED;
+}
+
 void DriveIntegrationService::DriveFsHolder::OnMounted(
     const base::FilePath& path) {
   on_drivefs_mounted_.Run();

chromeos/components/drivefs/drivefs_host.cc

@@ -165,7 +165,8 @@ class DriveFsHost::MountState : public mojom::DriveFsDelegate,
                       const std::vector<std::string>& scopes,
                       GetAccessTokenCallback callback) override {
     DCHECK_CALLED_ON_VALID_SEQUENCE(host_->sequence_checker_);
-    if (get_access_token_callback_) {
+    if (get_access_token_callback_ ||
+        !host_->delegate_->AreRefreshTokensReady()) {
       std::move(callback).Run(mojom::AccessTokenStatus::kTransientError, "");
       return;
     }

chromeos/components/drivefs/drivefs_host.h

@@ -59,6 +59,7 @@ class COMPONENT_EXPORT(DRIVEFS) DriveFsHost
     virtual net::URLRequestContextGetter* GetRequestContext() = 0;
     virtual service_manager::Connector* GetConnector() = 0;
     virtual const AccountId& GetAccountId() = 0;
+    virtual bool AreRefreshTokensReady() = 0;
     virtual std::unique_ptr<OAuth2MintTokenFlow> CreateMintTokenFlow(
         OAuth2MintTokenFlow::Delegate* delegate,
         const std::string& client_id,

chromeos/components/drivefs/drivefs_host_unittest.cc

@@ -109,7 +109,10 @@ class TestingDriveFsHostDelegate : public DriveFsHost::Delegate {
   TestingDriveFsHostDelegate(
       std::unique_ptr<service_manager::Connector> connector,
       const AccountId& account_id)
-      : connector_(std::move(connector)), account_id_(account_id) {}
+      : connector_(std::move(connector)), account_id_(account_id) {
+    ON_CALL(*this, AreRefreshTokensReady())
+        .WillByDefault(testing::Return(true));
+  }
 
   MockOAuth2MintTokenFlow& mock_flow() { return mock_flow_; }
 
@@ -119,6 +122,7 @@ class TestingDriveFsHostDelegate : public DriveFsHost::Delegate {
 
   // DriveFsHost::Delegate:
   MOCK_METHOD1(OnMounted, void(const base::FilePath&));
+  MOCK_METHOD0(AreRefreshTokensReady, bool());
 
  private:
   // DriveFsHost::Delegate:
@@ -567,6 +571,29 @@ TEST_F(DriveFsHostTest, GetAccessToken_SequentialRequests) {
   }
 }
 
+TEST_F(DriveFsHostTest, GetAccessToken_RefreshTokensNotReadyYet) {
+  ASSERT_NO_FATAL_FAILURE(DoMount());
+
+  EXPECT_CALL(*host_delegate_, AreRefreshTokensReady())
+      .WillOnce(testing::Return(false));
+  EXPECT_CALL(mock_identity_manager_,
+              GetAccessToken("test@example.com", _, "drivefs"))
+      .Times(0);
+  host_delegate_->mock_flow().ExpectNoStartCalls();
+
+  base::RunLoop run_loop;
+  auto quit_closure = run_loop.QuitClosure();
+  delegate_ptr_->GetAccessToken(
+      "client ID", "app ID", {"scope1", "scope2"},
+      base::BindLambdaForTesting(
+          [&](mojom::AccessTokenStatus status, const std::string& token) {
+            EXPECT_EQ(mojom::AccessTokenStatus::kTransientError, status);
+            EXPECT_TRUE(token.empty());
+            std::move(quit_closure).Run();
+          }));
+  run_loop.Run();
+}
+
 TEST_F(DriveFsHostTest, GetAccessToken_GetAccessTokenFailure_Permanent) {
   ASSERT_NO_FATAL_FAILURE(DoMount());