Drive: Mount/Unmount GoogleDrive on Files App when the file system is mounted/unmounted.

chrome/browser/chromeos/gdata/mock_gdata_file_system.h

Index: chrome/browser/chromeos/gdata/mock_gdata_file_system.h
diff --git a/chrome/browser/chromeos/gdata/mock_gdata_file_system.h b/chrome/browser/chromeos/gdata/mock_gdata_file_system.h
index 321bb4d30f538007e0d9e29713c9ad4ab74c93c4..2676ee568cf01b537dfb13538d20a0210f2f3555 100644
--- a/chrome/browser/chromeos/gdata/mock_gdata_file_system.h
+++ b/chrome/browser/chromeos/gdata/mock_gdata_file_system.h
@@ -24,6 +24,8 @@ class MockGDataFileSystem : public GDataFileSystemInterface {
   MOCK_METHOD1(RemoveObserver, void(Observer* observer));
   MOCK_METHOD0(StartUpdates, void());
   MOCK_METHOD0(StopUpdates, void());
+  MOCK_METHOD0(NotifyFileSystemMounted, void());
+  MOCK_METHOD0(NotifyFileSystemUnmounting, void());
   MOCK_METHOD0(CheckForUpdates, void());
   MOCK_METHOD2(GetEntryInfoByResourceId,
                void(const std::string& resource_id,
@@ -80,6 +82,8 @@ class MockGDataFileSystem : public GDataFileSystemInterface {
                void(const FilePath& file_path));
   MOCK_METHOD1(GetAvailableSpace,
                void(const GetAvailableSpaceCallback& callback));
+  MOCK_METHOD0(AddDriveMountPoint, void());
+  MOCK_METHOD0(RemoveDriveMountPoint, void());
   // This function is not mockable by gmock because scoped_ptr is not supported.
   virtual void AddUploadedFile(UploadMode upload_mode,
                                const FilePath& file,