Dispatch out-of-quota errors from DriveFS to DriveFsHostObservers.

Bug: 844298
Change-Id: I318dbeab7f0badd6d2cf06d22ddf197d590662af
Reviewed-on: https://chromium-review.googlesource.com/1196286Reviewed-by: Stuart Langley <slangley@chromium.org>
Commit-Queue: Sam McNally <sammc@chromium.org>
Cr-Commit-Position: refs/heads/master@{#587861}

chromeos/components/drivefs/drivefs_host.cc

@@ -221,6 +221,12 @@ class DriveFsHost::MountState : public mojom::DriveFsDelegate,
     }
   }
 
+  void OnError(mojom::DriveErrorPtr error) override {
+    for (auto& observer : host_->observers_) {
+      observer.OnError(*error);
+    }
+  }
+
   void OnConnectionError() {
     DCHECK_CALLED_ON_VALID_SEQUENCE(host_->sequence_checker_);
     if (!drivefs_has_terminated_) {

chromeos/components/drivefs/drivefs_host_observer.h

@@ -9,6 +9,7 @@
 
 namespace drivefs {
 namespace mojom {
+class DriveError;
 class FileChange;
 class SyncingStatus;
 }  // namespace mojom
@@ -18,6 +19,7 @@ class DriveFsHostObserver {
   virtual void OnUnmounted() {}
   virtual void OnSyncingStatusUpdate(const mojom::SyncingStatus& status) {}
   virtual void OnFilesChanged(const std::vector<mojom::FileChange>& changes) {}
+  virtual void OnError(const mojom::DriveError& error) {}
 
  protected:
   ~DriveFsHostObserver() = default;

chromeos/components/drivefs/drivefs_host_unittest.cc

@@ -233,6 +233,9 @@ class MockDriveFsHostObserver : public DriveFsHostObserver {
  public:
   MOCK_METHOD0(OnUnmounted, void());
   MOCK_METHOD1(OnSyncingStatusUpdate, void(const mojom::SyncingStatus& status));
+  MOCK_METHOD1(OnFilesChanged,
+               void(const std::vector<mojom::FileChange>& changes));
+  MOCK_METHOD1(OnError, void(const mojom::DriveError& error));
 };
 
 ACTION_P(RunQuitClosure, quit) {
@@ -775,8 +778,7 @@ ACTION_P(CloneStruct, output) {
   *output = arg0.Clone();
 }
 
-TEST_F(DriveFsHostTest,
-       GetAccessToken_OnSyncingStatusUpdate_ForwardToObservers) {
+TEST_F(DriveFsHostTest, OnSyncingStatusUpdate_ForwardToObservers) {
   ASSERT_NO_FATAL_FAILURE(DoMount());
   MockDriveFsHostObserver observer;
   ScopedObserver<DriveFsHost, DriveFsHostObserver> observer_scoper(&observer);
@@ -795,5 +797,49 @@ TEST_F(DriveFsHostTest,
   EXPECT_EQ(status, observed_status);
 }
 
+ACTION_P(CloneVectorOfStructs, output) {
+  for (auto& s : arg0) {
+    output->emplace_back(s.Clone());
+  }
+}
+
+TEST_F(DriveFsHostTest, OnFilesChanged_ForwardToObservers) {
+  ASSERT_NO_FATAL_FAILURE(DoMount());
+  MockDriveFsHostObserver observer;
+  ScopedObserver<DriveFsHost, DriveFsHostObserver> observer_scoper(&observer);
+  observer_scoper.Add(host_.get());
+  std::vector<mojom::FileChangePtr> changes;
+  changes.emplace_back(base::in_place, base::FilePath("/create"),
+                       mojom::FileChange::Type::kCreate);
+  changes.emplace_back(base::in_place, base::FilePath("/delete"),
+                       mojom::FileChange::Type::kDelete);
+  changes.emplace_back(base::in_place, base::FilePath("/modify"),
+                       mojom::FileChange::Type::kModify);
+  std::vector<mojom::FileChangePtr> observed_changes;
+  EXPECT_CALL(observer, OnFilesChanged(_))
+      .WillOnce(CloneVectorOfStructs(&observed_changes));
+  delegate_ptr_->OnFilesChanged(mojo::Clone(changes));
+  delegate_ptr_.FlushForTesting();
+  testing::Mock::VerifyAndClear(&observer);
+
+  EXPECT_EQ(changes, observed_changes);
+}
+
+TEST_F(DriveFsHostTest, OnError_ForwardToObservers) {
+  ASSERT_NO_FATAL_FAILURE(DoMount());
+  MockDriveFsHostObserver observer;
+  ScopedObserver<DriveFsHost, DriveFsHostObserver> observer_scoper(&observer);
+  observer_scoper.Add(host_.get());
+  auto error = mojom::DriveError::New(
+      mojom::DriveError::Type::kCantUploadStorageFull, base::FilePath("/foo"));
+  mojom::DriveErrorPtr observed_error;
+  EXPECT_CALL(observer, OnError(_)).WillOnce(CloneStruct(&observed_error));
+  delegate_ptr_->OnError(error.Clone());
+  delegate_ptr_.FlushForTesting();
+  testing::Mock::VerifyAndClear(&observer);
+
+  EXPECT_EQ(error, observed_error);
+}
+
 }  // namespace
 }  // namespace drivefs

chromeos/components/drivefs/mojom/drivefs.mojom

@@ -61,6 +61,9 @@ interface DriveFsDelegate {
 
   // Invoked when server-side file changes are received.
   OnFilesChanged(array<FileChange> changes);
+
+  // Invoked when a supported error occurs.
+  OnError(DriveError error);
 };
 
 struct DriveFsConfiguration {
@@ -103,6 +106,18 @@ enum FileError {
   kServiceUnavailable = -18,
 };
 
+// Errors received from DriveFS to be forwarded to the file manager UI.
+struct DriveError {
+  [Extensible] enum Type {
+    kCantUploadStorageFull,
+  };
+
+  Type type;
+
+  // The path to the file where an error was encountered, if there was one.
+  mojo_base.mojom.FilePath path;
+};
+
 struct FileMetadata {
   enum Type {
     // A regular file.