Internal error in ASBlockWalker subsystem, when generating code for mx.controls.RichTextEditor

```

/home/paulo/Repos/Flex4Royale/project/projects/mx/src/mx/controls/RichTextEditor.mxml line 275 column 4 Internal error in ASBlockWalker subsystem, when generating code for: /home/paulo/Repos/Flex4Royale/project/projects/mx/src/mx/controls/RichTextEditor.mxml line 275 column 4: java.lang.NullPointerException: Cannot assign field "value" because "ps" is null
at org.apache.royale.compiler.internal.codegen.mxml.royale.MXMLRoyaleEmitter.emitArray(MXMLRoyaleEmitter.java:3219)
at org.apache.royale.compiler.internal.codegen.mxml.MXMLBlockWalker.visitArray(MXMLBlockWalker.java:307)
at org.apache.royale.compiler.internal.visitor.mxml.MXMLNodeSwitch.handle(MXMLNodeSwitch.java:79)
at org.apache.royale.compiler.internal.codegen.mxml.MXMLBlockWalker.walk(MXMLBlockWalker.java:158)
at org.apache.royale.compiler.internal.codegen.mxml.royale.MXMLRoyaleEmitter.emitDocument(MXMLRoyaleEmitter.java:892)
at org.apache.royale.compiler.internal.codegen.mxml.royale.MXMLRoyaleBlockWalker.visitDocument(MXMLRoyaleBlockWalker.java:69)
at org.apache.royale.compiler.internal.visitor.mxml.MXMLNodeSwitch.handle(MXMLNodeSwitch.java:91)
at org.apache.royale.compiler.internal.codegen.mxml.MXMLBlockWalker.walk(MXMLBlockWalker.java:158)
at org.apache.royale.compiler.internal.codegen.mxml.royale.MXMLRoyaleBlockWalker.visitFile(MXMLRoyaleBlockWalker.java:61)
at org.apache.royale.compiler.internal.visitor.mxml.MXMLNodeSwitch.handle(MXMLNodeSwitch.java:97)
at org.apache.royale.compiler.internal.codegen.mxml.MXMLBlockWalker.walk(MXMLBlockWalker.java:158)
at org.apache.royale.compiler.internal.codegen.mxml.MXMLBlockWalker.visitCompilationUnit(MXMLBlockWalker.java:189)
at org.apache.royale.compiler.internal.codegen.mxml.MXMLWriter.writeTo(MXMLWriter.java:69)
at org.apache.royale.compiler.clients.COMPJSCNative.writeSWC(COMPJSCNative.java:399)
at org.apache.royale.compiler.clients.COMPJSCNative.compile(COMPJSCNative.java:201)
at org.apache.royale.compiler.clients.MXMLJSCNative._mainNoExit(MXMLJSCNative.java:248)
at org.apache.royale.compiler.clients.MXMLJSCNative.mainNoExit(MXMLJSCNative.java:205)
at org.apache.royale.compiler.clients.COMPJSC._mainNoExit(COMPJSC.java:203)
at org.apache.royale.compiler.clients.COMPJSC.mainNoExit(COMPJSC.java:119)
at org.apache.royale.compiler.clients.COMPJSC.staticMainNoExit(COMPJSC.java:104)
at org.apache.royale.compiler.clients.COMPJSC.main(COMPJSC.java:84)
```

Hello!

I have been trying to get Flex 4 working with OpenFL
I got textLayout and framework compiling by cheating a bit and using playerglobal.swc for library path instead of openfl's SWC
However mx does not compile properly, on SWF it works but JS it just throws an Internal Compiler Error.
Code is available here:
https://github.com/Fancy2209/Flex4Royale

Reproduce the JS compilation failure for projects/mx/src/mx/controls/RichTextEditor.mxml at line 275 using the MXMLJSCNative entry point. Start with MXMLRoyaleEmitter.emitArray, identified in the stack trace, and trace the null state during array emission. Done means the RichTextEditor MXML compiles for JS without the internal NullPointerException.

Written by the indexing model from the issue text.