[Runtime] Enable to update a web application from local

A web application can be updated from local when using "--install" switch
in command line, like this:
$ xwalk --install /path/to/xpk_package.xpk
If the application has been installed, WRT will try to update it.

https://crosswalk-project.org/jira/browse/XWALK-463
[Runtime] Re-factor for Install & Update methods in ApplicationService class
[application] Add a multiple applications test

Add an in-browser test making sure that running of multiple applications within XWalk runtime process works correctly.
Besides this patch contains a fix of a crash on Application exit (crash had been discovered with the newly added test).
Merge pull request #1491 from pozdnyakov/Add_Multi_App_Test

[application] Add a multiple applications test
Implement EventTarget interface for window.screen
Get or Set the property on the current holder (after load of extension)

An extension (and any web app for that matter) can replace objects in the DOM.
If this happens as part of lazy loading, it means that the property access
which triggered the lazy load, had its holder object replaced and the access
it thus being triggered on the original holder and not the current one (as
replaced by the extension).

This patch makes sure that we trigger it on the current holder.

Example:

We lazy load when accessing window.screen.height, so when that is accessed
the extension system loads the extension (which replaces window.screen of
type Screen with ReplacementScreen).

If the extension was not loaded lazily, window.screen.height would access
height on ReplacementScreen (the holder), but when lazily loaded Screen hasn't
been replaced when the access it being made. Thus we need to make sure that
we call height on the new holder immediately after loading the extension.
Merge pull request #1494 from kenchris/replace

Make the Screen object compatible with the Screen Orientation spec
Merge pull request #1396 from takethathe/update

[Runtime] Enable to update a web application from local
Add images for the wiki page explaining the rebase process.
DEPS.xwalk: Roll chromium-crosswalk to 438a2ac

[RE] Fix the crash issue caused by no memory for TLS slot allocation
[application] Use 'url' manifest key for launching "dummy" applications

Use 'url' manifest key for launching "dummy" applications (applications that were created internally
for rendering and arbitrary URL) instead of currently used 'app.launch.web_url'.

Spec: http://w3c.github.io/manifest/#url-member
Merge pull request #1508 from pozdnyakov/ChangeManifestKeyToURL

[application] Use 'url' manifest key for launching "dummy" applications
Merge pull request #1507 from hmin/update-deps

DEPS.xwalk: Roll chromium-crosswalk to 438a2ac
Revert "Merge pull request #1396 from takethathe/update"

The PR #1396 broke the build on Tizen.

This reverts commit 3fa5458b998020a1bf7fff34ee61b85f10ccf4ca, reversing
changes made to b1f193724ec58b419ae6596d9e629c3544034edd.
Merge pull request #1509 from vcgomes/tizen-application-update-revert

Revert "Merge pull request #1396 from takethathe/update"
[Application][Tizen] Move the installation steps into a new file

When running Crosswalk on Tizen in the 'run-as-service' mode we use
the new installation mode, that only a small binary will run as root.
[Packaging] Set the install helper tool as 'set-user-ID-root'

This will allow this tool to finish the last pieces of the installation
of an application: copying the icon to the right place and adding the
application meta-data to the central application database (via a XML
file that is also kept in a central place).
[Application][Tizen] Simplify the installation steps

We can keep the application binary (that will be a link to the xwalk-launcher)
binary inside a user created directory (data_dir), this allows for some
simplification.

Error are printed in the standard output, so the 'GetAppOutputWithExitCode()'
can print bettter error messages if installation/uninstallation fails.
[Application][Tizen] Change the effective UID of the application to 'root'

When adding the application metadata to the application
database (pkgmgr_parser_parse_manifest_for_installation), it is
required that the process has 'root'(0) UID so the
installation/uninstallation can proceed.
[Application][Tizen] Exit the application when the TERMINATE event is received

If we want the application to quit after it is terminated via the
Tizen task manager, we need to handle this event.

As Crosswalk will be following the unique name of the launcher process
and will kill the appropriate application when its launcher exits the
D-Bus session bus, simply calling exit() is enough.