The pointer of get() should check null or not.

Merge pull request !55 from Night/master

Merge pull request !56 from yu_qinfei/master

solve problem: open some apps in one time, one app in it can not open later.
Because, task_id and id in change-475ca1c8u is not similar.

The display is abnormal after the Ishenzhen is maximized,
it is recommended that the maximized be removed.

Merge pull request !53 from twwang/master

modify some bad coding style

Merge pull request !50 from Night/master

them until one.

When platform create window is not finished, multi_window_manager will post
more than one create window message event.
note: Windows destroy mast so user can not sense it.

Merge pull request !48 from rongwang/master

Merge pull request !49 from Night/master

we recognized that add lock will lose more time in submit_layers,
and that lock is unuseful. Remove this lock and use origin logic.

if data size is zero, we don`t need to write it down.
and it can also avoid a crash inside buffer queue.

Merge pull request !47 from yu_qinfei/master

The display is abnormal after the Himalaya is maximized,
it is recommended that the maximized be removed.

Merge pull request !46 from yu_qinfei/master

The origin apps supports ESC back window, but such as
TencentVideo app do not support it. Now, support it.

Merge pull request !45 from rongwang/master

Android manager color buffer by process,
so in Anbox in have to manager color buffer by
thread, instead of managing by Android itself.

1.call a virtual function in dtor will always get 0.
  so we can never destroy native_window_. adjust native_window_
  to /wm/window.h can solve this issue.
2.delete icon after SDL_SetWindowIcon, which is what SDL tell us
  to do in the official SDL documents.

Merge pull request !43 from Night/master

Solve Chinese input problem: can not input Chinese punctuation like '？', '》'...

continuously maximize window will crash some app, such as qqmusic...

Merge pull request !42 from zhdguy/master

when close Settings app with window back button or
after search back, activity views do not display.
And, search things will ANR crash and no search result.
This patch fixed above aborts.

Merge pull request !41 from Night/master

1.rename "register_event" -> "user_window_event",
  rename "get_register_event()" -> "get_user_window_event()".
2.add function user_event_function() to reduce Cyclomatic complexity of process_event
  in file platform/sdl/platform.cpp.
3.add Log when SDL_RegisterEvent return -1.
4.add lock in layer_composer.cpp:submit_layers to protect window in win_layers.

Add 5 test-UTs in multi_window_manager.cpp to test function below:
  1.insert_task.
  2.erase_task.
  3.apply_window_state_update.

Three test-UIs in layer_composer_tests.cpp failed on commit-d4579e95, and
the last is not suitable too(succeeded however).
It happens becase this commit changes function "apply_window_state_update"
in multi_window_manager.cpp.

Set ime socket path from /tmp/ime to socket_dir()/ime_socket.
note: socket on android system is ime as old. So no need to change android code.

Merge pull request !38 from Night/master

Add four window property:
  HIDE_BACK
  HIDE_CLOSE
  HIDE_MAXIMIZE
  HIDE_MINIMIZE

set qqmusic HIDE_BACK

note: if you change window property on anbox, you should change it on android at the same time.
change file on android: frameworks/base/core/java/com/android/internal/widget/DecorCaptionView.java

Merge pull request !35 from twwang/master

Merge pull request !31 from rongwang/master

Merge pull request !30 from rongwang/master

Merge pull request !28 from rongwang/N/A

Merge pull request !23 from twwang/N/A