mediaview: Implement ArcDocumentsProviderBackendDelegate.

chrome/browser/chromeos/arc/fileapi/arc_documents_provider_root.cc

 // Copyright 2016 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 "chrome/browser/chromeos/arc/fileapi/arc_documents_provider_root.h"
 
 #include "base/bind.h"
 #include "base/files/file.h"
 #include "base/logging.h"
 #include "base/memory/ptr_util.h"
@@ skipping 60 matching lines @@
   if (path.empty()) {
     ReadDirectoryAfterCacheUpdate(path, callback);
     return;
   }
   UpdateDirectoryCacheUpTo(
       StripBaseName(path),
       base::Bind(&ArcDocumentsProviderRoot::ReadDirectoryAfterCacheUpdate,
                  weak_ptr_factory_.GetWeakPtr(), path, callback));
 }
 
+void ArcDocumentsProviderRoot::ResolveToContentUrl(
+    const base::FilePath& path,
+    const ResolveToContentUrlCallback& callback) {
+  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+  // Skip a cache update if possible.
+  ArcDocumentsProviderDocument* entry = root_directory_->Lookup(path);
+  if (entry) {
+    ResolveToContentUrlAfterCacheUpdate(path, callback);
+    return;
+  }
+  UpdateDirectoryCacheUpTo(
+      path,
+      base::Bind(&ArcDocumentsProviderRoot::ResolveToContentUrlAfterCacheUpdate,
+                 weak_ptr_factory_.GetWeakPtr(), path, callback));
+}
+
 void ArcDocumentsProviderRoot::GetFileInfoAfterCacheUpdate(
     const base::FilePath& path,
     const GetFileInfoCallback& callback) {
   DCHECK_CURRENTLY_ON(BrowserThread::IO);
   ArcDocumentsProviderDocument* entry = root_directory_->Lookup(path);
   if (!entry) {
     callback.Run(base::File::FILE_ERROR_NOT_FOUND, base::File::Info());
     return;
   }
   file_system_instance_util::GetDocumentOnIOThread(
@@ skipping 59 matching lines @@
 
   std::vector<storage::DirectoryEntry> entry_list;
   for (const auto& pair : parent_directory->children()) {
     entry_list.emplace_back(pair.first, pair.second->is_directory()
                                             ? storage::DirectoryEntry::DIRECTORY
                                             : storage::DirectoryEntry::FILE);
   }
   callback.Run(base::File::FILE_OK, entry_list, false /* has_more */);
 }
 
+void ArcDocumentsProviderRoot::ResolveToContentUrlAfterCacheUpdate(
+    const base::FilePath& path,
+    const ResolveToContentUrlCallback& callback) {
+  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+  ArcDocumentsProviderDocument* entry = root_directory_->Lookup(path);
+  if (!entry) {
+    callback.Run(GURL());
+    return;
+  }
+  callback.Run(BuildDocumentUrl(authority_, entry->document_id()));
+}
+
 void ArcDocumentsProviderRoot::UpdateDirectoryCacheUpTo(
     const base::FilePath& path,
     const base::Closure& callback) {
   DCHECK_CURRENTLY_ON(BrowserThread::IO);
   UpdateDirectoryCacheIter(base::FilePath(), path, callback);
 }
 
 void ArcDocumentsProviderRoot::UpdateDirectoryCacheIter(
     const base::FilePath& parent_directory_path,
     const base::FilePath& remaining_path,
@@ skipping 48 matching lines @@
       parent_directory_path.Append(components[0]);
   base::FilePath next_remaining_path =
       base::FilePath::FromUTF8Unsafe(base::JoinString(
           Components(components.begin() + 1, components.end()), "/"));
 
   UpdateDirectoryCacheIter(next_parent_directory_path, next_remaining_path,
                            callback);
 }
 
 }  // namespace arc