fix: line nr in test name in wrong places

test.Test() overrides name() in order to provide source line number
information. However, overriding name() is the wrong place for that, as
name() is also often used for identifying an object - when listing the
tests of a suite, the line number should not appear in the test name.
For example, the line number sometimes ends up in the test results in
jenkins, making 'foo.py' and 'foo.py:23' two distinct report items.

Instead, add a separate function Origin.src() that defaults to name(),
but specific classes can override src() if they wish to provide more
detailed information with the object name.

Override src() in Test, not name().

Use src() in backtraces.

The suite_test.ok shows that the backtracing in the log remains
unchanged, but the place where the test name is printed is corrected:
   I am 'test_suite' / 'hello_world.py:23'
becomes
   I am 'test_suite' / 'hello_world.py'
(Notice that "[LINENR]" in suite_test.ok is a masking of an actual
number, done within the selftest suite)

Change-Id: I0c4698fa2b3db3de777d8b6dcdcee84e433c62b7
diff --git a/selftest/suite_test/suite_test.ok b/selftest/suite_test/suite_test.ok
index dfc8d41..2c49c19 100644
--- a/selftest/suite_test/suite_test.ok
+++ b/selftest/suite_test/suite_test.ok
@@ -160,7 +160,7 @@
 trial test_suite hello_world.py
 ----------------------------------------------
 tst hello_world.py:[LINENR]: hello world  [test_suite↪hello_world.py:[LINENR]]
-tst hello_world.py:[LINENR]: I am 'test_suite' / 'hello_world.py:[LINENR]'  [test_suite↪hello_world.py:[LINENR]]
+tst hello_world.py:[LINENR]: I am 'test_suite' / 'hello_world.py'  [test_suite↪hello_world.py:[LINENR]]
 tst hello_world.py:[LINENR]: one  [test_suite↪hello_world.py:[LINENR]]
 tst hello_world.py:[LINENR]: two  [test_suite↪hello_world.py:[LINENR]]
 tst hello_world.py:[LINENR]: three  [test_suite↪hello_world.py:[LINENR]]
@@ -187,7 +187,7 @@
 ----------------------------------------------
 trial test_suite test_error.py
 ----------------------------------------------
-tst test_error.py:[LINENR]: I am 'test_suite' / 'test_error.py:[LINENR]'  [test_suite↪test_error.py:[LINENR]]  [test_error.py:[LINENR]]
+tst test_error.py:[LINENR]: I am 'test_suite' / 'test_error.py'  [test_suite↪test_error.py:[LINENR]]  [test_error.py:[LINENR]]
 tst test_error.py:[LINENR]: ERR: AssertionError: test_error.py:[LINENR]: assert False  [test_suite↪test_error.py:[LINENR]]  [test_error.py:[LINENR]: assert False]
 tst test_error.py:[LINENR]: Test FAILED (N.N sec)  [test_suite↪test_error.py:[LINENR]]  [test.py:[LINENR]]
 ---------------------------------------------------------------------
@@ -212,7 +212,7 @@
 ----------------------------------------------
 trial test_suite test_fail.py
 ----------------------------------------------
-tst test_fail.py:[LINENR]: I am 'test_suite' / 'test_fail.py:[LINENR]'  [test_suite↪test_fail.py:[LINENR]]  [test_fail.py:[LINENR]]
+tst test_fail.py:[LINENR]: I am 'test_suite' / 'test_fail.py'  [test_suite↪test_fail.py:[LINENR]]  [test_fail.py:[LINENR]]
 tst test_fail.py:[LINENR]: ERR: EpicFail: This failure is expected  [test_suite↪test_fail.py:[LINENR]]  [test_fail.py:[LINENR]]
 tst test_fail.py:[LINENR]: Test FAILED (N.N sec)  [test_suite↪test_fail.py:[LINENR]]  [test.py:[LINENR]]
 ---------------------------------------------------------------------
@@ -389,7 +389,7 @@
 trial test_suite hello_world.py
 ----------------------------------------------
 tst hello_world.py:[LINENR]: hello world  [test_suite↪hello_world.py:[LINENR]]  [hello_world.py:[LINENR]]
-tst hello_world.py:[LINENR]: I am 'test_suite' / 'hello_world.py:[LINENR]'  [test_suite↪hello_world.py:[LINENR]]  [hello_world.py:[LINENR]]
+tst hello_world.py:[LINENR]: I am 'test_suite' / 'hello_world.py'  [test_suite↪hello_world.py:[LINENR]]  [hello_world.py:[LINENR]]
 tst hello_world.py:[LINENR]: one  [test_suite↪hello_world.py:[LINENR]]  [hello_world.py:[LINENR]]
 tst hello_world.py:[LINENR]: two  [test_suite↪hello_world.py:[LINENR]]  [hello_world.py:[LINENR]]
 tst hello_world.py:[LINENR]: three  [test_suite↪hello_world.py:[LINENR]]  [hello_world.py:[LINENR]]
@@ -544,7 +544,7 @@
 trial test_suite hello_world.py
 ----------------------------------------------
 tst hello_world.py:[LINENR]: hello world  [test_suite↪hello_world.py:[LINENR]]  [hello_world.py:[LINENR]]
-tst hello_world.py:[LINENR]: I am 'test_suite' / 'hello_world.py:[LINENR]'  [test_suite↪hello_world.py:[LINENR]]  [hello_world.py:[LINENR]]
+tst hello_world.py:[LINENR]: I am 'test_suite' / 'hello_world.py'  [test_suite↪hello_world.py:[LINENR]]  [hello_world.py:[LINENR]]
 tst hello_world.py:[LINENR]: one  [test_suite↪hello_world.py:[LINENR]]  [hello_world.py:[LINENR]]
 tst hello_world.py:[LINENR]: two  [test_suite↪hello_world.py:[LINENR]]  [hello_world.py:[LINENR]]
 tst hello_world.py:[LINENR]: three  [test_suite↪hello_world.py:[LINENR]]  [hello_world.py:[LINENR]]
@@ -745,7 +745,7 @@
 trial test_suite hello_world.py
 ----------------------------------------------
 tst hello_world.py:[LINENR]: hello world  [test_suite↪hello_world.py:[LINENR]]  [hello_world.py:[LINENR]]
-tst hello_world.py:[LINENR]: I am 'test_suite' / 'hello_world.py:[LINENR]'  [test_suite↪hello_world.py:[LINENR]]  [hello_world.py:[LINENR]]
+tst hello_world.py:[LINENR]: I am 'test_suite' / 'hello_world.py'  [test_suite↪hello_world.py:[LINENR]]  [hello_world.py:[LINENR]]
 tst hello_world.py:[LINENR]: one  [test_suite↪hello_world.py:[LINENR]]  [hello_world.py:[LINENR]]
 tst hello_world.py:[LINENR]: two  [test_suite↪hello_world.py:[LINENR]]  [hello_world.py:[LINENR]]
 tst hello_world.py:[LINENR]: three  [test_suite↪hello_world.py:[LINENR]]  [hello_world.py:[LINENR]]