Allow linking of library jars in building apk targets

Allow linking of library jars in building apk targets

Added a library_jars_paths variable for building apk
targets to allow embedders to build apks that depend
on custom platform libraries.

BUG=

Committed: https://crrev.com/015499d2758f53fd1fde45f02b99d34d96a3323e
Cr-Commit-Position: refs/heads/master@{#351327}

[ctserng, 2015-09-22 19:01:35]

tserng@amazon.com changed reviewers:
+ jbudorick@chromium.org

[ctserng, 2015-09-22 19:01:35]

PTAL

[ctserng, 2015-09-28 14:22:40]

On 2015/09/22 at 19:01:35, ctserng wrote:
> PTAL

ping

[jbudorick, 2015-09-29 09:13:44]

This generally looks fine, but I'm curious: what's the motivation here?

(I ask because I've got a patchset locally that adds something similar with the
intention of using it in multidex, but that's been blocked on other problems.)

[ctserng, 2015-09-29 13:40:56]

On 2015/09/29 at 09:13:44, jbudorick wrote:
> This generally looks fine, but I'm curious: what's the motivation here?
> 
> (I ask because I've got a patchset locally that adds something similar with
the intention of using it in multidex, but that's been blocked on other
problems.)

The motivation here is the ability to build an APK that uses a shared library
that is declared using the <uses-library> element in the manifest.  There does
not seem to be a way to specify a library to link against while excluding the
classes from the final APK.

[jbudorick, 2015-09-29 13:44:35]

I was wondering about a more specific use case -- this CL obviously doesn't use
this gyp variable at all.

https://codereview.chromium.org/1355323003/diff/1/build/java_apk.gypi
File build/java_apk.gypi (right):

https://codereview.chromium.org/1355323003/diff/1/build/java_apk.gypi#newcode79
build/java_apk.gypi:79: 'library_jars_paths': [],
can we initialize this to 

  [ <(android_sdk_jar) ]

and omit android_sdk_jar from the --classpath argument below?

[ctserng, 2015-09-29 13:53:40]

On 2015/09/29 at 13:44:35, jbudorick wrote:
> I was wondering about a more specific use case -- this CL obviously doesn't
use this gyp variable at all.
> 
> https://codereview.chromium.org/1355323003/diff/1/build/java_apk.gypi
> File build/java_apk.gypi (right):
> 
>
https://codereview.chromium.org/1355323003/diff/1/build/java_apk.gypi#newcode79
> build/java_apk.gypi:79: 'library_jars_paths': [],
> can we initialize this to 
> 
>   [ <(android_sdk_jar) ]
> 
> and omit android_sdk_jar from the --classpath argument below?

The gyp variable is used in our customizations.  We customize SystemWebView
target to add some features that are available in a shared library on our
platform.  So I think it would be generically useful to others wishing to do
similar things.

[ctserng, 2015-09-29 13:54:34]

https://codereview.chromium.org/1355323003/diff/1/build/java_apk.gypi
File build/java_apk.gypi (right):

https://codereview.chromium.org/1355323003/diff/1/build/java_apk.gypi#newcode79
build/java_apk.gypi:79: 'library_jars_paths': [],
On 2015/09/29 at 13:44:35, jbudorick wrote:
> can we initialize this to 
> 
>   [ <(android_sdk_jar) ]
> 
> and omit android_sdk_jar from the --classpath argument below?

I'm not sure we can do this because the intention is for the top-level target to
define library_jars_paths, in which case this would force them to have to
remember to add 'android_sdk_jar' as well.

That being said, it's already included in the --bootclasspath so I'm wondering
if it might not even be necessary at all in --classpath?  (I'm not that familiar
with the difference in the 2 options).

[jbudorick, 2015-09-29 13:59:28]

lgtm

https://codereview.chromium.org/1355323003/diff/1/build/java_apk.gypi
File build/java_apk.gypi (right):

https://codereview.chromium.org/1355323003/diff/1/build/java_apk.gypi#newcode79
build/java_apk.gypi:79: 'library_jars_paths': [],
On 2015/09/29 at 13:54:33, ctserng wrote:
> On 2015/09/29 at 13:44:35, jbudorick wrote:
> > can we initialize this to 
> > 
> >   [ <(android_sdk_jar) ]
> > 
> > and omit android_sdk_jar from the --classpath argument below?
> 
> I'm not sure we can do this because the intention is for the top-level target
to define library_jars_paths, in which case this would force them to have to
remember to add 'android_sdk_jar' as well.
> 
> That being said, it's already included in the --bootclasspath so I'm wondering
if it might not even be necessary at all in --classpath?  (I'm not that familiar
with the difference in the 2 options).

AFAICT the two are different.

[ctserng, 2015-09-29 14:01:02]

The CQ bit was checked by tserng@amazon.com

[commit-bot: I haz the power, 2015-09-29 14:01:35]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1355323003/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1355323003/1

[commit-bot: I haz the power, 2015-09-29 16:12:31]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-09-29 16:13:52]

Patchset 1 (id:??) landed as
https://crrev.com/015499d2758f53fd1fde45f02b99d34d96a3323e
Cr-Commit-Position: refs/heads/master@{#351327}