Add a HideStdout() method to our TestBase class and call it from TestAbbreviations.py
and TestAliases.py.  Pass the keyword argument 'check=False' to:

    self.runCmd("script my.date()", check=False)

since we want to restore sys.stdout no matter what the outcome of the runCmd is.

llvm-svn: 129949
diff --git a/lldb/test/command_source/TestCommandSource.py b/lldb/test/command_source/TestCommandSource.py
index bd4493f..4c8404a 100644
--- a/lldb/test/command_source/TestCommandSource.py
+++ b/lldb/test/command_source/TestCommandSource.py
@@ -27,7 +27,8 @@
         sys.stdout = session
 
         # Python should evaluate "my.date()" successfully.
-        self.runCmd("script my.date()")
+        # Pass 'check=False' so that sys.stdout gets restored unconditionally.
+        self.runCmd("script my.date()", check=False)
 
         # Now restore stdout to the way we were. :-)
         sys.stdout = old_stdout