catch_command_errors: Remove 'mask' parameter

catch_command_errors: Remove 'mask' parameter

All callers of catch_command_errors pass RETURN_MASK_ALL as mask
argument.  This patch eliminates the mask parameter as unnecessary.

gdb/ChangeLog:
2015-02-27  Pedro Alves  <palves@redhat.com>

	* main.c (catch_command_errors, catch_command_errors_const):
	Remove 'mask' argument.  Adjust.
	(captured_main): Adjust callers.

gdb/testsuite/ChangeLog:
2015-02-27  Pedro Alves  <palves@redhat.com>

	* gdb.gdb/python-interrupts.exp (test_python_interrupts): Adjust
	call to catch_command_errors.
	* gdb.gdb/python-selftest.exp (selftest_python): Adjust call to
	catch_command_errors.