Add test for bug already fixed by the refactoring.

ChangeLog

@@ -27,6 +27,8 @@ some minor bugs and Perl incompatibilities were fixed, including:
       the name "DEFINE" exists. PCRE2 now does likewise.
   (d) A recursion condition test such as (?(R2)...) must now refer to an 
       existing subpattern.
+  (e) A conditional recursion test such as (?(R)...) misbehaved if there was a 
+      group whose name began with "R".
 
 One effect of the refactoring is that some error numbers and messages have 
 changed, and the pattern offset given for compiling errors is not always the

testdata/testinput2

@@ -4888,4 +4888,8 @@ a)"xI
 /[a-\d]+/
     a-a9-a
 
+/(?<RA>abc)(?(R)xyz)/B
+
+/(?<R>abc)(?(R)xyz)/B
+
 # End of testinput2 

testdata/testoutput2

@@ -15306,6 +15306,34 @@ Failed: error 150 at offset 4: invalid range in character class
 Failed: error 150 at offset 5: invalid range in character class
     a-a9-a
 
+/(?<RA>abc)(?(R)xyz)/B
+------------------------------------------------------------------
+        Bra
+        CBra 1
+        abc
+        Ket
+        Cond
+        Cond recurse any
+        xyz
+        Ket
+        Ket
+        End
+------------------------------------------------------------------
+
+/(?<R>abc)(?(R)xyz)/B
+------------------------------------------------------------------
+        Bra
+        CBra 1
+        abc
+        Ket
+        Cond
+      1 Cond ref
+        xyz
+        Ket
+        Ket
+        End
+------------------------------------------------------------------
+
 # End of testinput2 
 Error -63: PCRE2_ERROR_BADDATA (unknown error number)
 Error -62: bad serialized data