[3rd tvOS]tvos commands

[KazuCocoa]

Final PR for #148 as implementing features for tvOS.
As WDA, we can handle tvOS via WDA after this PR.

We need to add tvOS support in xcuitest-driver.

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curl -X GET http://localhost:8100/session/493E964A-FD36-4B34-9AF0-97698B0FE907/wda/element/focused # get a focused element

# After find element. e.g. 17000000-0000-0000-7E6D-000000000000
curl -X POST http://localhost:8100/session/493E964A-FD36-4B34-9AF0-97698B0FE907/element/6B030000-0000-0000-7E6D-000000000000/focuse -d '' # Work via inspector
curl -X GET http://localhost:8100/session/493E964A-FD36-4B34-9AF0-97698B0FE907/element/6B030000-0000-0000-7E6D-000000000000/focused # Work

# For compatibility of clients. Clients can get `focus` status as `get attribute` API
curl -X GET http://localhost:8100/session/493E964A-FD36-4B34-9AF0-97698B0FE907/element/6B030000-0000-0000-7E6D-000000000000/attribute/focused # Work

# Worked. We can click an element on TV.
# Users can do selecting action via `click` as same as iOS
curl -X POST http://localhost:8100/session/493E964A-FD36-4B34-9AF0-97698B0FE907/element/6B030000-0000-0000-7E6D-000000000000/click -d ''

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hasFocus was only in tvOS. So I've added ifdef for tvOS again.
I'll add unit tests as next PR since it needs to add new test targets and test classes.

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New endpoints

• [[FBRoute GET:@"/element/:uuid/attribute/focused"] respondWithTarget:self action:@selector(handleGetFocused:)],
  • Get an attribute of 'focused'
• [[FBRoute POST:@"/wda/element/:uuid/focuse"] respondWithTarget:self action:@selector(handleFocuse:)],
  • Set a focus to an element which is :uuid
• [[FBRoute GET:@"/wda/element/focused"] respondWithTarget:self action:@selector(handleFindFocusedElement:)],
  • Get an element which is focused

[KazuCocoa]

added New endpoints section in the description

[KazuCocoa]

@shvul
Hi, I would share this with you.
Your FB's tvOS support PR has been merged into appium fork with some modifications.
Thanks so much.
appium/appium-xcuitest-driver#911

[shvul]

@KazuCocoa
Wow! That's amazing!
Thanks a lot!