Merge CrosDisksClientStubImpl into FakeCrosDisksClient

Merge CrosDisksClientStubImpl into FakeCrosDisksClient

Move the fake mounting logic from CrosDisksClientStubImpl
to FakeCrosDsisksClient, with some simplification.

The fake behaviors are used in FileManagerBrowserTest's
OpenZipFiles test. The test is currently disabled for
a performance reason, but I've confirmed that the test
passes with --gtest_also_run_disabled_tests.

TEST=out/Release/browser_tests --gtest_filter='*OpenZipFiles*' --gtest_also_run_disabled_tests
BUG=309506
Committed: https://crrev.com/8fd29380c9f675f931121080c22a4fef520140f5
Cr-Commit-Position: refs/heads/master@{#302053}

[satorux1, 2014-10-29 05:42:20]

satorux@chromium.org changed reviewers:
+ hashimoto@chromium.org

[hashimoto, 2014-10-29 06:43:53]

lgtm

https://codereview.chromium.org/676423004/diff/20001/chromeos/dbus/fake_cros_...
File chromeos/dbus/fake_cros_disks_client.cc (right):

https://codereview.chromium.org/676423004/diff/20001/chromeos/dbus/fake_cros_...
chromeos/dbus/fake_cros_disks_client.cc:19: static MountError
PerformFakeMount(const std::string& source_path,
nit: "static" unneeded.

[satorux1, 2014-10-29 06:47:02]

https://codereview.chromium.org/676423004/diff/20001/chromeos/dbus/fake_cros_...
File chromeos/dbus/fake_cros_disks_client.cc (right):

https://codereview.chromium.org/676423004/diff/20001/chromeos/dbus/fake_cros_...
chromeos/dbus/fake_cros_disks_client.cc:19: static MountError
PerformFakeMount(const std::string& source_path,
On 2014/10/29 06:43:53, hashimoto wrote:
> nit: "static" unneeded.

Done.

[hashimoto, 2014-10-29 06:47:57]

lgtm

[satorux1, 2014-10-30 07:40:31]

The CQ bit was checked by satorux@chromium.org

[commit-bot: I haz the power, 2014-10-30 07:41:38]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/676423004/40001

[commit-bot: I haz the power, 2014-10-30 08:23:22]

Committed patchset #3 (id:40001)

[commit-bot: I haz the power, 2014-10-30 08:23:59]

Patchset 3 (id:??) landed as
https://crrev.com/8fd29380c9f675f931121080c22a4fef520140f5
Cr-Commit-Position: refs/heads/master@{#302053}