[Android] Add navigation handler for handling platform-specific schemes.

Some platform-specific schemes are needed to be handled, eg, "wtai://", we
provide default navigation handler in XWalkView to support such schemes.

"wtai://" is a protocol scheme that can initiate a dialog with the mobile phone
user whether to place a call to that number, send an SMS message, or store the
number in the address list of the mobile phone.

See: http://www.w3.org/wiki/UriSchemes/wtai

In this patch we support placing a call. And other functions will be added later.

BUG=https://github.com/crosswalk-project/crosswalk/issues/380
[Android] Enable app customize/build tools works on Window Host.

Original customize/build tools are only verified on Linux Host.
They have some environment assumptions for Linux, which would
break the app build on Windows Host. What's more,
there are also some differences for default behavior of build tools,
such as: ant etc. This patch will fill the gap, make app
customize/build tools works on Window Host.

1. Fix the different path separator on different OS host.
2. Fix different default ant behavior on diefferent OS host.
3. Fix different extension for executable binary on different OS host.
4. Fix python subprocess work different on different OS host.

BUG=https://github.com/crosswalk-project/crosswalk/issues/616
[Extensions][Windows] Enable ExtensionProcess for Windows
Bump chromium-crosswalk in DEPS.xwalk.

Bring in fixing in android testing facility for emulater support.
[Android] Add reload getTitle clearHistory in XWalkView for internal use
- Load: reload
- UI: getTitle
- Navigation: clearHistory
- Add stop, reload buttons in XWalkViewShellActivity
- Add testcase for reload, clearHistory
Clean up in use of DesktopRootWindowHostXWalk

DesktopRootWindowHostXWalk serves as our "desktop environment"
per scree, which is somewhat similar to the X11 window manager
concept.

The specialized version of DesktopRootWindowHost (*XWalk) in
our situation, is created as part of DesktopNativeWidgetAura
initialization, but requires build system changes for doing so.

This patch cleans up part of the code, making it very clear
why we manually creates DesktopRootWindowHostXWalk and why it
works. It also removes the ::Create method which is called
by DesktopRootWindowHost because it is wrongly named, and if
named correctly it will conflict with the symbol from *X11.
Use unsigned int for data comparison inside ASSERT_GE()

Buildbot reports warning message "C4018: '>=' : signed/unsigned
mismatch" if the arguments of function ASSERT_GE() have different types.
Since runtimes.size() returns an unsigned int value, this CL changes the
other value to the same type for comparison.
Merge pull request #702 from shaochangbin/browsertest

Use unsigned int for data comparison inside ASSERT_GE()
Merge pull request #661 from sqliu/otcshare-handle-wtai

[Android] Add navigation handler for handling platform-specific schemes.
[Tizen] Integrate crosswalk with Tizen input method system.

Crosswalk needs to be integrated with Tizen input system,
so that users could e.g., enter text into input field element.

This CL integrates chromium input method system with Tizen IME
using SCIM / ISF (Input Service Framework) interfaces. SCIM is
running as a daemon and communicates with clients over socket.
Whenever client is asking to show input panel (VKB), input panel
is shown and key presses are sent back to the client over socket.
This CL implements basic functionality that will be extended in
following input method patches. Crosswalk opens virtual keyboard
and user can type-in latin characters. Unicode characters,
pre-editing and other advanced features are not implemented.

InputMethodScim - Realization of chromium InputMethod interface.
ScimBridge - Class that communicates with Tizen ISF and forwards key
events to chromium input method / text clients.
Merge pull request #681 from alexshalamov/integrate_tizen_ime

[Tizen] Integrate crosswalk with Tizen input method system.
Merge pull request #701 from kenchris/cleanupaura

Clean up in use of DesktopRootWindowHostXWalk
[Tizen] Add pkgconfig(scim) to the list of crosswalk dependencies.
Merge pull request #710 from alexshalamov/add_scim_dependency

[Tizen] Add pkgconfig(scim) to the list of crosswalk dependencies.
Update the documentation about Sync Messages

Now it is made clear that replies to Sync Messages can be sent after
the handler of the call has returned.

This is valid because we can only have one Sync Message going on at
any time (the renderer is blocking).
Merge pull request #712 from vcgomes/execution-model-docs

Update the documentation about Sync Messages
Clean the house in XWalkExtension(Instance)

- Updated the comments to be more on par with existing implementation;
- Added an overview at the top;
- Removed unused includes, forward declarations;
- Moved Callback types to XWalkExtensionInstance;
- Shuffled some functions to their appropriate places.

This patch shouldn't change code behavior.
Rename XWalkExternalContext to XWalkExternalInstance

The concept is now called Instance instead of Context. This allow us to
remove the typedef hack in XWalkExternalAdapter.
Rename xwalk_external_context.cc/h to xwalk_external_instance.cc/h

To match the class names. Patches are separated so the name change in
code is easier to review. This patch just renames the files and updates
references to it.
[Tizen] Use InputMethodSCIM instead of InputMethodScim in factory.