[lldb/test] Fix TestFunctionStarts for eee887e0

lldb/test/API/macosx/function-starts/TestFunctionStarts.py

@@ -37,10 +37,7 @@ class FunctionStartsTestCase(TestBase):
 
         exe = self.getBuildArtifact(exe_name)
         # Now strip the binary, but leave externals so we can break on dont_strip_me.
-        try:
-            fail_str = system([["strip", "-u", "-x", "-S", exe]])
-        except CalledProcessError as cmd_error:
-            self.fail("Strip failed: %d"%(cmd_error.returncode))
+        self.runBuildCommand(["strip", "-u", "-x", "-S", exe])
 
         # Use a file as a synchronization point between test and inferior.
         pid_file_path = lldbutil.append_to_process_working_directory(self,