Use WKWebView instead of deprecatd UIWebView

[mman]

Replaces usage of as UIWebView deprecated since iOS 8 with WKWebView.

This allows Bolts-ObjC to continue being built as a subproject or via Carthage for iOS 13, macOS 10.15 and macCatalyst 13.

[noobs2ninjas]

Hey mman.
Looks like we got a error on the iOS test.

Testing failed:
"OBJC_CLASS$_WKWebView", referenced from:
Linker command failed with exit code 1 (use -v to see invocation)
** TEST FAILED **

[mman]

Looking at that, I'm not sure how exactly travis does things, but I have tried to link both tests and Bolts with WebKit.framework so let's see what happens.

[codecov-io]

Codecov Report

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The diff coverage is n/a.

@@            Coverage Diff            @@
##             master       #1   +/-   ##
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  Coverage          ?   99.16%           
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  Files             ?        8           
  Lines             ?      478           
  Branches          ?        0           
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  Hits              ?      474           
  Misses            ?        4           
  Partials          ?        0

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[noobs2ninjas]

@mman

So I think what needs to happen is we need to update travis config file to use Xcode 11. I think its using an Xcode environment from before WKWebView was a thing. Also, we need to remove or update the code coverage.

Also, we need to go ahead and remove the iOS only files anyway from the macOS build. Think you could go through each targets build phase and check to see that those file say iOS only? Seems on Xcode 11 that most iOS only targets get converted to catalyst and added "macOS + iOS" to every single file on the "Compile Sources" list.

Heres what I mean:

[noobs2ninjas]

In fact this change alone probably would have fixed our builds. Once you get this done I'll update the podspec and carthage on Parse and ParseLiveQuery.

[noobs2ninjas]

@mman Im going to go ahead and merge this. The errors are coming from xctest signing which isnt an issue with your code at that point.

[noobs2ninjas]

Hey @mman. Could you take a look at my closed pull request. I updated the project to build with Xcode 11 and all the sudden some tests started breaking dealing with app linking. I commented those out and updated a few other things to get our tests passing.

[mman]

Hi @noobs2ninjas, what exactly do you want me to check out please? I'm not that familar with the build infrastructure yet. Please send me a link and I'll take a look. Thanks.

[noobs2ninjas]

@mman I think we are ok at this point. Getting parse to build just fine with this fork.

[mman]

Excellent, I plan to get back to this stuff during the next weeks, will re-test as well. Great job and thanks for merging! Martin.