message: Split TestVLA into two and XFAIL one part
  The part which checks whether vla_expr shows up in the variable list
  does not pass on non-darwin platforms. Add the appropriate decorator.
diff: import lldb
  from lldbsuite.test.lldbtest import *
  -from lldbsuite.test import decorators
  +from lldbsuite.test.decorators import *
  import lldbsuite.test.lldbutil as lldbutil
  @@ -8,8 +8,9 @@ class TestVLA(TestBase):
  mydir = TestBase.compute_mydir(__file__)
  - @decorators.skipIf(compiler="clang", compiler_version=['<', '8.0'])
  - def test_vla(self):
  + @skipIf(compiler="clang", compiler_version=['<', '8.0'])
  + @expectedFailureAll(oslist=no_match(lldbplatformutil.getDarwinOSTriples()))
  + def test_variable_list(self):
  self.build()
  _, process, _, _ = lldbutil.run_to_source_breakpoint(
  self, "break here", lldb.SBFileSpec('main.c'))
  @@ -26,6 +27,12 @@ class TestVLA(TestBase):
  for value in all_locals:
  self.assertFalse("vla_expr" in value.name)
  + @decorators.skipIf(compiler="clang", compiler_version=['<', '8.0'])
  + def test_vla(self):
  + self.build()
  + _, process, _, _ = lldbutil.run_to_source_breakpoint(
  + self, "break here", lldb.SBFileSpec('main.c'))
  +
  def test(a, array):
  for i in range(a):
  self.expect("fr v vla[%d]"%i, substrs=["int", "%d"%(a-i)])
  