[Extensions] Add support for persistent callback listener

This is going to be the base of the EventTarget implementation. It is
important to remove the listener at some point otherwise the object will
leak.
[Extensions] Add browsertests for the persistent callback listener

The test implements a heartbeat which works in a similar way of an EventTarget.
The callback is set only one and gets called multiple times.
[Extensions] Remove development debug statements

These debugging statements were useful during development, but now
as we are feeling confident that everything should be working, they
can be removed.
Merge pull request #1039 from vcgomes/remove-development-debugs

[Extensions] Remove development debug statements
Merge pull request #1038 from tmpsantos/persistent_callback

[Extensions] Support for persistent callback
Add a patcher script to apply patches

1. Patcher is a helper to apply patches to certain repos.
2. It runs in hooks of DEPS after fetching deps successfully.
3. patch.cfg is used to config the patch path and target repo path.
4. These python scripts origin from CEF project.
[Tizen] Device motion/orientation API

Chromium has device motion/orientation API support, but not on Tizen.
To leverage chromium's code, an xwalk::DataFetcherSharedMemory object
is created to bridge xwalk and chromium. This object acts as a sensor
event listener of xwalk and writes sensor data into chromium's shared
memory.

SPEC: http://www.w3.org/TR/orientation-event/
Merge pull request #1051 from xingnan/patcher

Add a patcher script to apply patches
[Android] Destroy the native resource of XWalkView

Each XWalkContnet object owned by XWalkView has its own native counterpart, we
need to cleanup the native resource when an XWalkContent object is requested to
be destroyed, e.g. an activity is destroyed.

This fix is to add 'destroy' method to XWalkContent for this purpose.

BUG=https://github.com/crosswalk-project/crosswalk/issues/998
[Android] Add loadAssetFileAndWaitForTitle and apply in XWalkCoreTest cases

Instrumentation tests may fail because the titles may be verified
before they are changed. This commit introduced a new interface named
"loadAssetFileAndWaitForTitle" to wait until the title be changed.

BUG=#984 (Partially)
[Android] Refactor the code for instrumentation tests.

Currently so many source codes are duplicated and hard to maintain.
Need to refactor them and share common code. This fix is to share
all common code in utils so that instrumentation tests for embedded
and shared modes can share as many code as possible.
This is the second step. The next one is to share the code for core
tests.

BUG=https://crosswalk-project.org/jira/browse/XWALK-95
[Android] Use loadAppFromManifest if a manifest.json is used for a web app.

Add loadAppFromManifest support for web app. If web app is packaged with
manifest, directly use loadAppFromManifest API to load app.
Because native manifest parser only supports original proposal
"app:launch:local_path", manifest related test cases are modified.
When the specfication for manifest is stable, will revisit these test
cases and native manifest parser.

BUG=https://crosswalk-project.org/jira/browse/XWALK-100?filter=10007
Merge pull request #1044 from junmin-zhu/manifest

[Android] Use loadAppFromManifest if a manifest.json is used for a web app
Merge pull request #1037 from DonnaWuDongxia/waitForTitle

[Android] Add loadAssetFileAndWaitForTitle and apply in XWalkCoreTest cases
Merge pull request #1050 from hmin/destroy-xwalkview

[Android] Destroy the native resource of XWalkContent
Merge pull request #1054 from yongsheng/refactorcodetest

[Android] Refactor the code for instrumentation tests.
Merge pull request #966 from zliang7/dev

[Tizen] Device motion/orientation API
[Tizen] Enforce device scale factor value to '2.0' on Tizen

Enforce device scale factor value to '2.0' on Tizen so that viewport meta tag works properly on Tizen devices.
This is a workaround until Aura Linux HIDPI support is in place: https://codereview.chromium.org/27156003/.