Remove ComponentLoader's unnecessary string copy.

Remove ComponentLoader's unnecessary string copy.

ComponentLoader::Add(int manifest_id, ...) is how most components extensions
get added. Couple of exceptions are: pdf_extension and IME. Otherwise,
ComponentLoader::Add gets the resource from ResourceBundle and then converts the
StringPiece representing the resource to std::string (copy) and feeds them to
ComponentLoader::ParseManifest().
ParseManifest construct a StringPiece from the std::string since
JSONStringValueDeserializer is capable of working with StringPiece-s.

This CL removes the intermediate conversion from StringPiece to string for
most of the cases.
This probably helps chormeos more than non-chromeos, since I saw 30 component
extension being loaded through ComponentLoader resulting in 49254 bytes
of unnecessary copy.

BUG=638775
Test=No observable change. FYI: this can affect built in chromeos extensions.

Committed: https://crrev.com/3cdbf74891491f09473f87ebf215d327ff27296d
Cr-Commit-Position: refs/heads/master@{#412719}

[lazyboy, 2016-08-17 23:29:02]

lazyboy@chromium.org changed reviewers:
+ asargent@chromium.org

[lazyboy, 2016-08-17 23:30:26]

The CQ bit was checked by lazyboy@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2016-08-17 23:30:47]

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

[asargent_no_longer_on_chrome, 2016-08-17 23:53:00]

nice catch, lgtm

[commit-bot: I haz the power, 2016-08-18 01:05:51]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2016-08-18 01:05:52]

Dry run: This issue passed the CQ dry run.

[lazyboy, 2016-08-18 01:24:16]

The CQ bit was checked by lazyboy@chromium.org

[commit-bot: I haz the power, 2016-08-18 01:24:43]

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, 2016-08-18 01:29:27]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-08-18 01:32:30]

Description was changed from

==========
Remove ComponentLoader's unnecessary string copy.

ComponentLoader::Add(int manifest_id, ...) is how most components extensions
get added. Couple of exceptions are: pdf_extension and IME. Otherwise,
ComponentLoader::Add gets the resource from ResourceBundle and then converts the
StringPiece representing the resource to std::string (copy) and feeds them to
ComponentLoader::ParseManifest().
ParseManifest construct a StringPiece from the std::string since
JSONStringValueDeserializer is capable of working with StringPiece-s.

This CL removes the intermediate conversion from StringPiece to string for
most of the cases.
This probably helps chormeos more than non-chromeos, since I saw 30 component
extension being loaded through ComponentLoader resulting in 49254 bytes
of unnecessary copy.

BUG=638775
Test=No observable change. FYI: this can affect built in chromeos extensions.
==========

to

==========
Remove ComponentLoader's unnecessary string copy.

ComponentLoader::Add(int manifest_id, ...) is how most components extensions
get added. Couple of exceptions are: pdf_extension and IME. Otherwise,
ComponentLoader::Add gets the resource from ResourceBundle and then converts the
StringPiece representing the resource to std::string (copy) and feeds them to
ComponentLoader::ParseManifest().
ParseManifest construct a StringPiece from the std::string since
JSONStringValueDeserializer is capable of working with StringPiece-s.

This CL removes the intermediate conversion from StringPiece to string for
most of the cases.
This probably helps chormeos more than non-chromeos, since I saw 30 component
extension being loaded through ComponentLoader resulting in 49254 bytes
of unnecessary copy.

BUG=638775
Test=No observable change. FYI: this can affect built in chromeos extensions.

Committed: https://crrev.com/3cdbf74891491f09473f87ebf215d327ff27296d
Cr-Commit-Position: refs/heads/master@{#412719}
==========

[commit-bot: I haz the power, 2016-08-18 01:32:31]

Patchset 1 (id:??) landed as
https://crrev.com/3cdbf74891491f09473f87ebf215d327ff27296d
Cr-Commit-Position: refs/heads/master@{#412719}