[iOS] Should not process key events in non-editable elements using IME

[Daniel Bates]

Attach Chinese/Japanese hardware keyboard.

Steps to reproduce:

1. Visit <https://unixpapa.com/js/testkey.html>
2. Press 'a'

You should see output like:

keydown  keyCode=65  (A)   which=65  (A)   charCode=0        
keypress keyCode=97  (a)   which=97  (a)   charCode=97  (a)  
keyup    keyCode=65  (A)   which=65  (A)   charCode=0        

But I see:

keydown  keyCode=229       which=229       charCode=0        
         shiftKey=false ctrlKey=false altKey=false metaKey=false
         key=a char=undefined location=0 repeat=false
keyup    keyCode=65  (A)   which=65  (A)   charCode=0        
         shiftKey=false ctrlKey=false altKey=false metaKey=false
         key=a char=undefined location=0 repeat=false

[Radar WebKit Bug Importer]

<rdar://problem/52006654>

[Daniel Bates]

Created attachment 372660 [details]
Patch

[Brent Fulgham]

Comment on attachment 372660 [details]
Patch

Looks good -- now we match macOS behavior. r=me

[Daniel Bates]

Comment on attachment 372660 [details]
Patch

Clearing flags on attachment: 372660

Committed r246810: <https://trac.webkit.org/changeset/246810>

[Daniel Bates]

All reviewed patches have been landed.  Closing bug.