Avoid unnecessary copies in ImageDecoder.

Avoid unnecessary copies in ImageDecoder.

For the deprecated API methods with const std::string&
parameter, copy is reduced from two times to once.

With the new API methods with std::vector<uint8_t>
parameter, the caller can avoid copies at all by passing
data with std::move().

Also converts ArcWallpaperHandler to use the new API
as a first user.

BUG=631327
TEST=browser_tests --gtest_filter='ImageDecoderBrowserTest.*'

Committed: https://crrev.com/601d970a8b243166000aab822b779e66a0d3760e
Cr-Commit-Position: refs/heads/master@{#407861}

[Shuhei Takahashi, 2016-07-25 09:52:56]

nya@chromium.org changed reviewers:
+ thestig@chromium.org

[Shuhei Takahashi, 2016-07-25 09:52:57]

thestig: PTAL

[Lei Zhang, 2016-07-25 18:41:32]

Looking good.

- Is there a bug # for this?
- Do you want to start converting at least one caller in chrome/ in this CL?

[Shuhei Takahashi, 2016-07-26 06:13:05]

Description was changed from

==========
Reduce unnecessary copies in ImageDecoder.

For the deprecated API methods with const std::string&
parameter, copy is reduced from two times to once.

With the new API methods with std::vector<uint8_t>
parameter, the caller can avoid copies at all by passing
data with std::move().

BUG=None
TEST=browser_tests --gtest_filter='ImageDecoderBrowserTest.*'
==========

to

==========
Avoid unnecessary copies in ImageDecoder.

For the deprecated API methods with const std::string&
parameter, copy is reduced from two times to once.

With the new API methods with std::vector<uint8_t>
parameter, the caller can avoid copies at all by passing
data with std::move().

BUG=631327
TEST=browser_tests --gtest_filter='ImageDecoderBrowserTest.*'
==========

[Shuhei Takahashi, 2016-07-26 07:49:40]

Description was changed from

==========
Avoid unnecessary copies in ImageDecoder.

For the deprecated API methods with const std::string&
parameter, copy is reduced from two times to once.

With the new API methods with std::vector<uint8_t>
parameter, the caller can avoid copies at all by passing
data with std::move().

BUG=631327
TEST=browser_tests --gtest_filter='ImageDecoderBrowserTest.*'
==========

to

==========
Avoid unnecessary copies in ImageDecoder.

For the deprecated API methods with const std::string&
parameter, copy is reduced from two times to once.

With the new API methods with std::vector<uint8_t>
parameter, the caller can avoid copies at all by passing
data with std::move().

Also converts ArcWallpaperHandler to use the new API
as a first user.

BUG=631327
TEST=browser_tests --gtest_filter='ImageDecoderBrowserTest.*'
==========

[Shuhei Takahashi, 2016-07-26 07:51:51]

nya@chromium.org changed reviewers:
+ hidehiko@chromium.org

[Shuhei Takahashi, 2016-07-26 07:51:51]

thestig: PTAL all
hidehiko: PTAL at arc changes

I've changed ArcWallpaperHandler as a first user of the new API. Also I filed a
crbug for this issue.

[hidehiko, 2016-07-26 07:56:29]

*/arc/* lgtm.

[Lei Zhang, 2016-07-26 17:58:15]

lgtm

[Lei Zhang, 2016-07-26 17:58:19]

The CQ bit was checked by thestig@chromium.org

[commit-bot: I haz the power, 2016-07-26 17:58:46]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-07-26 18:39:40]

Description was changed from

==========
Avoid unnecessary copies in ImageDecoder.

For the deprecated API methods with const std::string&
parameter, copy is reduced from two times to once.

With the new API methods with std::vector<uint8_t>
parameter, the caller can avoid copies at all by passing
data with std::move().

Also converts ArcWallpaperHandler to use the new API
as a first user.

BUG=631327
TEST=browser_tests --gtest_filter='ImageDecoderBrowserTest.*'
==========

to

==========
Avoid unnecessary copies in ImageDecoder.

For the deprecated API methods with const std::string&
parameter, copy is reduced from two times to once.

With the new API methods with std::vector<uint8_t>
parameter, the caller can avoid copies at all by passing
data with std::move().

Also converts ArcWallpaperHandler to use the new API
as a first user.

BUG=631327
TEST=browser_tests --gtest_filter='ImageDecoderBrowserTest.*'
==========

[commit-bot: I haz the power, 2016-07-26 18:39:41]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2016-07-26 18:43:53]

Description was changed from

==========
Avoid unnecessary copies in ImageDecoder.

For the deprecated API methods with const std::string&
parameter, copy is reduced from two times to once.

With the new API methods with std::vector<uint8_t>
parameter, the caller can avoid copies at all by passing
data with std::move().

Also converts ArcWallpaperHandler to use the new API
as a first user.

BUG=631327
TEST=browser_tests --gtest_filter='ImageDecoderBrowserTest.*'
==========

to

==========
Avoid unnecessary copies in ImageDecoder.

For the deprecated API methods with const std::string&
parameter, copy is reduced from two times to once.

With the new API methods with std::vector<uint8_t>
parameter, the caller can avoid copies at all by passing
data with std::move().

Also converts ArcWallpaperHandler to use the new API
as a first user.

BUG=631327
TEST=browser_tests --gtest_filter='ImageDecoderBrowserTest.*'

Committed: https://crrev.com/601d970a8b243166000aab822b779e66a0d3760e
Cr-Commit-Position: refs/heads/master@{#407861}
==========

[commit-bot: I haz the power, 2016-07-26 18:43:54]

Patchset 2 (id:??) landed as
https://crrev.com/601d970a8b243166000aab822b779e66a0d3760e
Cr-Commit-Position: refs/heads/master@{#407861}