[lldb] Update regex to be less fragile in TestDataFormatterGenericUnordered

[kastiglione]

Summary

Follow up to D129386 where libc++ naming conventions were made consistent.

This changes the pattern to not rely on the internal name (__cc or __cc_),
and instead uses a pattern to check that the child has the form:

[0] = {
  first = ...

Thanks to @rupprecht for pointing out this issue: https://reviews.llvm.org/D133259#3773120

lldb/test/API/functionalities/data-formatter/data-formatter-stl/generic/unordered/TestDataFormatterGenericUnordered.py

def do_test_with_run_command(self, stdlib_type):
         def cleanup():
             self.runCmd('type format clear', check=False)
             self.runCmd('type summary clear', check=False)
             self.runCmd('type filter clear', check=False)
             self.runCmd('type synth clear', check=False)
             self.runCmd(
                 "settings set target.max-children-count 256",
                 check=False)
+            self.runCmd(
+                'settings set auto-one-line-summaries true',
+                check=False)
 
         # Execute the cleanup function during test case tear down.
         self.addTearDownHook(cleanup)
 
         ns = self.namespace
 
         # We check here that the map shows 0 children even with corrupt data.
         self.look_for_content_and_continue(
             "corrupt_map", ['%s::unordered_map' %
                     ns, 'size=0 {}'])
 
-        must_not_contain__cc = r'(?s)^(?!.*\b__cc = )'
+        # Ensure key/value children, not wrapped in a layer.
+        # This regex depends on auto-one-line-summaries.
+        self.runCmd('settings set auto-one-line-summaries false')
+        children_are_key_value = r'\[0\] = \{\s*first = '
 
         self.look_for_content_and_continue(
             "map", ['%s::unordered_map' % ns,
-                    must_not_contain__cc,
+                    children_are_key_value,
                     'size=5 {', 'hello', 'world', 'this', 'is', 'me'])
 
         self.look_for_content_and_continue(
             "mmap", ['%s::unordered_multimap' % ns,
-                     must_not_contain__cc,
+                     children_are_key_value,
                      'size=6 {', 'first = 3', 'second = "this"',
                      'first = 2', 'second = "hello"'])
 
         self.look_for_content_and_continue(
             "iset", ['%s::unordered_set' %
                      ns, 'size=5 {', '\[\d\] = 5', '\[\d\] = 3', '\[\d\] = 2'])
 
         self.look_for_content_and_continue(