[Android] Customize the resource loading of MediaPlayer

Add XWalkMediaPlayerResourceLoadingFilter which inherits
MediaPlayerBridge.ResourceLoadingFilter. Then we can customize
the MediaPlayer in xwalk. Now we have two customized items:
    Support app scheme in the resource loading of MediaPlayer.
    Support file://android_asset/ url in MediaPlayer.

BUG=https://crosswalk-project.org/jira/browse/XWALK-880
[Android] Fix the issue of enabling remote debugging in packaging tool.

Remote debugging cannot work when the application is packaged with
--enable-remote-debugging for that remote debugging is disabled when
manifest.json file is used. This patch fixes this issue by removing
the related code of disabling remote debugging in packaging tool.
And the corresponding test case is added.

BUG=https://crosswalk-project.org/jira/browse/XWALK-933
Merge pull request #1569 from ShDavidliu/remote_debugging

[Android] Fix the issue of enabling remote debugging in packaging tool.
[Android] Add the application version in the package file name.

It is useful for the application developer to know which version of the
web application was packaged. This patch allows the published to add that
information while packaging the application by adding the handling process
of the application version in the packaging tool for shared mode and embedded
mode.

BUG=https://crosswalk-project.org/jira/browse/XWALK-908
[Android] Implement the onReceivedError callback.

Add the implementation of onReceivedError callback for XWalkClient
to fix the testUrl test case failed in crosswalk-cordova-android.
And remove error code from XWalkClient, which is originally from
AOSP WebView.
[Android] Only force enabling WebGL for Android on IA.

We've tested the WebGL conformance test and it's very good. For other
platforms, just follow up the behaviors defined by Chromium upstream
to avoid crashes.

BUG=https://crosswalk-project.org/jira/browse/XWALK-934
Merge pull request #1538 from ShDavidliu/PackageNameAppVersion

[Android] Add the application version in the package file name.
[Android] Add execution permission for python scripts.

All these scripts should have execution permission so that they
can be ran like below:
./make_apk.py ...

BUG=https://crosswalk-project.org/jira/browse/XWALK-935
Merge pull request #1573 from yongsheng/filep

[Android] Add execution permission for python scripts.
Merge pull request #1280 from junmin-zhu/error

[Android] Implement the onReceivedError callback.
Merge pull request #1572 from yongsheng/fix934

[Android] Only force enabling WebGL for Android on IA.
[Application] Added permission getter/setters in applicaiton

Added session and persistent permission getter/setters. Also moved
permission policy manager into application system. Moved permission
initialization logic out of application data, i.e. the application
data won't initialize itself.

[Application] Add permission check logic in application

This method is used to check API Control. It queries permissions
 actions from policy storage and tell the result to extension.
Merge pull request #1571 from mbbill/permission_3

[Application] Added permission check logic and getter/setters in application classes.
Bump version to 5.32.88.0
[Android] Fix that window.close is not working

Webapp might use window.close() to exit app.
This commit turns on the setting to allow this
usage and finish the activity when calling
window.close().

BUG=https://crosswalk-project.org/jira/browse/XWALK-939
[Android] Expose fullscreen related API to XWalkView

It's for embedder to customize the behavior of fullscreen
exiting in a flexible way.

BUG=https://crosswalk-project.org/jira/browse/XWALK-954
Merge pull request #1578 from wang16/window_close

[Android] Fix that window.close is not working
Merge pull request #1580 from wang16/view_fullscreen_api

[Android] Expose fullscreen related API to XWalkView
[Android] Launch Screen 1st-step implementation

This is the first step implementation of Launch Screen feature.

The workflow in general as below:
Build script:
1. Check whether 'launch-screen' provided in manifest.json.
2. Check 'launch-screen'->'default'->'image' field, and copy the image to 'res/drawable'
   Rename it as 'launchscreen.*'.
3. Set '@drawable/launchscreen' as window background, it will be displayed immediately
   after user tap the app icon.
Note: The drawable will be customized as the spec in the next implementation steps.

Runtime:
1. Check and get 'launch-screen'->'ready_when' field in manifest.json.
2. Display a dialog as launch screen, and set the background '@drawable/launchscreen'.
3. Hide the dialog depends on 'ready_when' condition:
   1. First rendered frame.
   2. First rendered frame & Page load finished
   3. First rendered frame & js:window.show()

TODO:
Test will be committed in another patch
Next step implementation will support the full spec.

Spec: https://docs.google.com/a/intel.com/document/d/17PuNuHRTQuREUpaCvj-eEx7uYi2avd-VW-oaMXMpvwo/edit?pli=1#
Design Doc: https://docs.google.com/a/intel.com/document/d/1YLajlZC7CkBOtEvzD6p6yeBr0HrPsaIGX8Eqhr3oTF4/edit#heading=h.mfsu3bk9566e
Bug: XWALK-637
Remove AUTHORS.

It has never been properly enforced and it does not have any effect for us.

We don't require a CLA, and we don't mention "The Crosswalk Authors" or
anything like that in the copyright headers on files.

Anyone can just send their patches and add their names as copyright holders
to the headers in the files they touch if the contributions are big enough.