Add FakeDriveURLRequestInfoInterface, an FakeFileIoInterface instance, &
FakeDriveURLResponseInfoInterface::GetProperty() to
FakePepperInterfaceGoogleDriveFs, and fix a reference count cycle issue
in FakePepperInterfaceGoogleDriveFs. FakePepperInterfaceGoogleDriveFs
is going to be used by the unit tests of the future code.
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_nacl_sdk;master.tryserver.chromium.mac:mac_nacl_sdk;master.tryserver.chromium.win:win_nacl_sdk
Review-Url: https://codereview.chromium.org/2573523004
Cr-Commit-Position: refs/heads/master@{#440605}