Add the chrome.fileSystem.onVolumeListChanged event.

chrome/browser/extensions/api/file_system/file_system_apitest_chromeos.cc

Index: chrome/browser/extensions/api/file_system/file_system_apitest_chromeos.cc
diff --git a/chrome/browser/extensions/api/file_system/file_system_apitest_chromeos.cc b/chrome/browser/extensions/api/file_system/file_system_apitest_chromeos.cc
index 3195a199a04247b4b33975444809698efabb407b..37cf8c60e8087b6d5a0ea482e720694a9fada00f 100644
--- a/chrome/browser/extensions/api/file_system/file_system_apitest_chromeos.cc
+++ b/chrome/browser/extensions/api/file_system/file_system_apitest_chromeos.cc
@@ -4,9 +4,12 @@
 
 #include "chrome/browser/extensions/api/file_system/file_system_api.h"
 
+#include "base/callback.h"
 #include "base/files/file_util.h"
 #include "base/files/scoped_temp_dir.h"
+#include "base/location.h"
 #include "base/path_service.h"
+#include "base/thread_task_runner_handle.h"
 #include "chrome/browser/apps/app_browsertest_util.h"
 #include "chrome/browser/chromeos/drive/drive_integration_service.h"
 #include "chrome/browser/chromeos/drive/file_system_interface.h"
@@ -18,7 +21,9 @@
 #include "chrome/browser/drive/fake_drive_service.h"
 #include "chrome/browser/extensions/component_loader.h"
 #include "chrome/common/chrome_paths.h"
+#include "chrome/common/extensions/api/file_system.h"
 #include "content/public/test/test_utils.h"
+#include "extensions/browser/event_router.h"
 #include "google_apis/drive/drive_api_parser.h"
 #include "google_apis/drive/test_util.h"
 #include "storage/browser/fileapi/external_mount_points.h"
@@ -36,6 +41,9 @@ const char kReadOnlyMountPointName[] = "read-only";
 // Child directory created in each of the mount points.
 const char kChildDirectory[] = "child-dir";
 
+// ID of a testing extension.
+const char kTestingExtensionId[] = "pkplfbidichfdicaijlchgnapepdginl";
+
 }  // namespace
 
 // Skips the user consent dialog for chrome.fileSystem.requestFileSystem() and
@@ -55,6 +63,41 @@ class ScopedSkipRequestFileSystemDialog {
   DISALLOW_COPY_AND_ASSIGN(ScopedSkipRequestFileSystemDialog);
 };
 
+// Observers adding a listener to the |event_name| event by |extension|, and
+// then fires the |callback|.
+class ScopedAddListenerObserver : public EventRouter::Observer {
+ public:
+  ScopedAddListenerObserver(Profile* profile,
+                            const std::string& event_name,
+                            const std::string& extension_id,
+                            const base::Closure& callback)
+      : extension_id_(extension_id),
+        callback_(callback),
+        event_router_(EventRouter::EventRouter::Get(profile)) {
+    DCHECK(profile);
+    DCHECK(event_router_);
+    event_router_->RegisterObserver(this, event_name);
+  }
+
+  ~ScopedAddListenerObserver() { event_router_->UnregisterObserver(this); }
+
+  // EventRouter::Observer overrides.
+  void OnListenerAdded(const EventListenerInfo& details) override {
+    // Call the callback only once, as the listener may be added multiple times.
+    if (details.extension_id == extension_id_ && !callback_.is_null()) {
+      base::ThreadTaskRunnerHandle::Get()->PostTask(FROM_HERE, callback_);
+      callback_ = base::Closure();
+    }
+  }
+
+ private:
+  const std::string extension_id_;
+  base::Closure callback_;
+  EventRouter* const event_router_;
+
+  DISALLOW_COPY_AND_ASSIGN(ScopedAddListenerObserver);
+};
+
 // This class contains chrome.filesystem API test specific to Chrome OS, namely,
 // the integrated Google Drive support.
 class FileSystemApiTestForDrive : public PlatformAppBrowserTest {
@@ -181,6 +224,16 @@ class FileSystemApiTestForRequestFileSystem : public PlatformAppBrowserTest {
     fake_user_manager_ = nullptr;
   }
 
+  // Simulates mounting a removable volume.
+  void MountFakeVolume() {
+    VolumeManager* const volume_manager =
+        VolumeManager::Get(browser()->profile());
+    ASSERT_TRUE(volume_manager);
+    volume_manager->AddVolumeForTesting(
+        base::FilePath("/a/b/c"), file_manager::VOLUME_TYPE_TESTING,
+        chromeos::DEVICE_TYPE_UNKNOWN, false /* read_only */);
+  }
+
  protected:
   base::ScopedTempDir temp_dir_;
   chromeos::FakeChromeUserManager* fake_user_manager_;
@@ -191,7 +244,6 @@ class FileSystemApiTestForRequestFileSystem : public PlatformAppBrowserTest {
                                bool read_only) {
     const base::FilePath mount_point_path =
         temp_dir_.path().Append(mount_point_name);
-    LOG(ERROR) << mount_point_path.value();
     ASSERT_TRUE(base::CreateDirectory(mount_point_path));
     ASSERT_TRUE(
         base::CreateDirectory(mount_point_path.Append(kChildDirectory)));
@@ -423,4 +475,18 @@ IN_PROC_BROWSER_TEST_F(FileSystemApiTestForRequestFileSystem,
       << message_;
 }
 
+IN_PROC_BROWSER_TEST_F(FileSystemApiTestForRequestFileSystem,
+                       OnVolumeListChanged) {
+  EnterKioskSession();
+
+  ScopedAddListenerObserver observer(
+      profile(), extensions::api::file_system::OnVolumeListChanged::kEventName,
+      kTestingExtensionId,
+      base::Bind(&FileSystemApiTestForRequestFileSystem::MountFakeVolume,
+                 this));
+
+  ASSERT_TRUE(RunPlatformAppTest("api_test/file_system/on_volume_list_changed"))
+      << message_;
+}
+
 }  // namespace extensions