Switch postcircumfix angles over.

Following STD more closely here seems to get us passing a few TODO'd
tests also.

src/Perl6/Actions.pm

@@ -4539,8 +4539,10 @@ class Perl6::Actions is HLL::Actions does STDActions {
 
     method postcircumfix:sym<ang>($/) {
         my $past := QAST::Op.new( :name('postcircumfix:<{ }>'), :op('callmethod'), :node($/) );
-        $past.push( $<quote_EXPR>.ast )
-            if +$<quote_EXPR><quote_delimited><quote_atom> > 0;
+        my $nib  := $<nibble>.ast;
+        $past.push($nib)
+            unless nqp::istype($nib, QAST::Stmts) && nqp::istype($nib[0], QAST::Op) &&
+            $nib[0].name eq '&infix:<,>' && +@($nib[0]) == 0;
         make $past;
     }
 

src/Perl6/Grammar.pm

@@ -2822,7 +2822,13 @@ grammar Perl6::Grammar is HLL::Grammar does STD {
     }
 
     token postcircumfix:sym<ang> {
-        <?[<]> <quote_EXPR: ':q', ':w'>
+        '<'
+        [
+        || <nibble(self.quote_lang(%*LANG<Q>, "<", ">", ['q', 'w']))> '>'
+        || <?before \h* [ \d | <sigil> | ':' ] >
+           { $/.CURSOR.panic("Whitespace required before < operator") }
+        || { $/.CURSOR.panic("Unable to parse quote-words subscript; couldn't find right angle quote") }
+        ]
         <O('%methodcall')>
     }