Merge remote-tracking branch 'origin/ios-official' into HEAD

Merging strategy "ours"

feat: Support script hash parameter in debugger protocol

DevTools in Chrome 76 uses it to set breakpoints of dynamic
`eval`-ed scripts.

fix: Do not send source parsed events on attach.

Here they are randomly ordered and this causes
NativeScript/ios-jsc#1158. All sources will be sent by
NativeScript on debugger enable event in GlobalObjectDebuggerAgent::enable() and the
order there will be the correct one because they are taken from module loader's registry.

fix: Prevent 2nd destructor call from ThreadSafeRefCounted

It can happen in the following scenario:

* `worker.js`:
```JS
let o = NSNotificationCenter.defaultCenter.addObserverForNameObjectQueueUsingBlock('send-to-worker', null, null, (obj) => {
setTimeout(() => {
    console.log('closing');
    NSNotificationCenter.defaultCenter.removeObserver(o);
    //u.releaseNativeObject(o); // crashes without this
    close();
}, 10 * 1000);
});

* `app.js`
```JS
var worker = new Worker("./worker.js");
```

refs NativeScript/ios-jsc#1137 (comment)

Update WebKit from iOS 12.3 release

https://trac.webkit.org/log/webkit/releases/Apple/iOS%2012.3/JavaScriptCore

The whole source tree is copied from the corresponding tag https://svn.webkit.org/repository/webkit/tags/Safari-607.2.6.0.1

Update WebKit from iOS 12.2 release

https://trac.webkit.org/log/webkit/releases/Apple/iOS%2012.2/JavaScriptCore

The whole source tree is copied from the corresponding tag https://svn.webkit.org/repository/webkit/tags/Safari-607.1.40.0.7

fix: Remove duplicate callstack in `console.trace` messages

{N} console trace messages already include the callstack because
we want it to be present in the Chrome debugger as well.

fix: Remove duplicate callstack in `console.trace` messages

{N} console trace messages already include the callstack because
we want it to be present in the Chrome debugger as well.

fix: Remove duplicate callstack in `console.trace` messages

{N} console trace messages already include the callstack because
we want it to be present in the Chrome debugger as well.

Make additional stamp files for LLIntAssembly.h per configuration

It seems like changing the build configuration also needs to regenerate
the low level interpreter. If it's not regenerated we receive a linker
error similar to:

```
Undefined symbols for architecture arm64:
  "_llint_entry", referenced from:
      JSC::LLInt::initialize() in libJavaScriptCore.a(UnifiedSource86.o)
     (maybe you meant: _llint_entry_osr_function_for_call_arityCheck, _llint_entry_osr_function_for_construct , _llint_entry_osr , _llint_entry_osr_function_for_construct_arityCheck , _llint_entry_osr_function_for_call )
  "_vmEntryToNative", referenced from:
      JSC::Interpreter::executeCall(JSC::ExecState*, JSC::JSObject*, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&) in libJavaScriptCore.a(UnifiedSource78.o)
      JSC::Interpreter::executeConstruct(JSC::ExecState*, JSC::JSObject*, JSC::ConstructType, JSC::ConstructData const&, JSC::ArgList const&, JSC::JSValue) in libJavaScriptCore.a(UnifiedSource78.o)
  "_llintPCRangeStart", referenced from:
      JSC::LLInt::isLLIntPC(void*) in libJavaScriptCore.a(UnifiedSource123.o)
  "_sanitizeStackForVMImpl", referenced from:
      JSC::sanitizeStackForVM(JSC::VM*) in libJavaScriptCore.a(UnifiedSource123.o)
  "_vmEntryRecord", referenced from:
      JSC::ExecState::callerFrame(JSC::EntryFrame*&) in libJavaScriptCore.a(UnifiedSource78.o)
      JSC::ExecState::unsafeCallerFrame(JSC::EntryFrame*&) in libJavaScriptCore.a(UnifiedSource78.o)
      JSC::StackVisitor::StackVisitor(JSC::ExecState*, JSC::VM*) in libJavaScriptCore.a(UnifiedSource78.o)
      JSC::UnwindFunctor::copyCalleeSavesToEntryFrameCalleeSavesBuffer(JSC::StackVisitor&) const in libJavaScriptCore.a(UnifiedSource78.o)
      JSC::EntryFrame::vmEntryRecordOffset() in libJavaScriptCore.a(UnifiedSource79.o)
      JSC::DFG::prepareOSREntry(JSC::ExecState*, JSC::CodeBlock*, unsigned int) in libJavaScriptCore.a(UnifiedSource48.o)
      JSC::DFG::restoreCalleeSavesFromVMEntryFrameCalleeSavesBuffer(JSC::Probe::Context&) in libJavaScriptCore.a(UnifiedSource48.o)
      ...
  "_llintPCRangeEnd", referenced from:
      JSC::LLInt::isLLIntPC(void*) in libJavaScriptCore.a(UnifiedSource123.o)
  "_vmEntryToJavaScript", referenced from:
      JSC::JITCode::execute(JSC::VM*, JSC::ProtoCallFrame*) in libJavaScriptCore.a(UnifiedSource120.o)
      JSC::vmEntryToWasm(void*, JSC::VM*, JSC::ProtoCallFrame*) in libJavaScriptCore.a(UnifiedSource86.o)
ld: symbol(s) not found for architecture arm64
```