Optimize parameters of list thumbnail loader for MTP volume.

Optimize parameters of list thumbnail loader for MTP volume.

On MTP volume, file operations are processed in the queue.
If we enqueue a lot of thumbnail loading tasks, it can make the queue full and block other operations (e.g. directory read).
In order not to block other operations, minimize the number of enqueued thumbnail loading on MTP volume.

BUG=468623
TEST=out/Release/browser_tests --gtest_filter=FileManagerJsTest.ListThumbnailLoader

Committed: https://crrev.com/81b8ccb5a93811db4738de9d8b6bfb2f03428591
Cr-Commit-Position: refs/heads/master@{#321315}

[yawano, 2015-03-19 07:10:39]

yawano@chromium.org changed reviewers:
+ hirono@chromium.org

[yawano, 2015-03-19 07:10:40]

PTAL. Thank you!

[hirono, 2015-03-19 07:53:04]

lgtm!

https://codereview.chromium.org/1002493003/diff/1/ui/file_manager/file_manage...
File ui/file_manager/file_manager/foreground/js/list_thumbnail_loader.js
(right):

https://codereview.chromium.org/1002493003/diff/1/ui/file_manager/file_manage...
ui/file_manager/file_manager/foreground/js/list_thumbnail_loader.js:114: *
@return {number} Number of prefetch requests.
nit: Usually the order of annotation is @param -> @return -> @private in
Files.app.

[yawano, 2015-03-19 07:57:47]

Thank you!

https://codereview.chromium.org/1002493003/diff/1/ui/file_manager/file_manage...
File ui/file_manager/file_manager/foreground/js/list_thumbnail_loader.js
(right):

https://codereview.chromium.org/1002493003/diff/1/ui/file_manager/file_manage...
ui/file_manager/file_manager/foreground/js/list_thumbnail_loader.js:114: *
@return {number} Number of prefetch requests.
On 2015/03/19 07:53:04, hirono wrote:
> nit: Usually the order of annotation is @param -> @return -> @private in
> Files.app.

Done.

[yawano, 2015-03-19 07:57:59]

The CQ bit was checked by yawano@chromium.org

[yawano, 2015-03-19 07:57:59]

The patchset sent to the CQ was uploaded after l-g-t-m from hirono@chromium.org
Link to the patchset: https://codereview.chromium.org/1002493003/#ps20001
(title: "Fix annotations order.")

[commit-bot: I haz the power, 2015-03-19 07:58:13]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1002493003/20001

[commit-bot: I haz the power, 2015-03-19 08:24:38]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2015-03-19 08:25:17]

Patchset 2 (id:??) landed as
https://crrev.com/81b8ccb5a93811db4738de9d8b6bfb2f03428591
Cr-Commit-Position: refs/heads/master@{#321315}