[test] Work around Android linker warning in message tests

Bug: chromium:1099623
Change-Id: Icbb6b0ebcc10628fafbef57cc6d1af7861e408f4
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2270170Reviewed-by: Maya Lekova <mslekova@chromium.org>
Reviewed-by: Tamer Tas <tmrts@chromium.org>
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#68561}

tools/testrunner/outproc/base.py

@@ -193,7 +193,7 @@ class ExpectedOutProc(OutProc):
             line.startswith('**') or
             line.startswith('ANDROID') or
             line.startswith('###') or
-            # TODO(machenbach): Android linker warning.
+            # Android linker warning.
             line.startswith('WARNING: linker:') or
             # FIXME(machenbach): The test driver shouldn't try to use slow
             # asserts if they weren't compiled. This fails in optdebug=2.

tools/testrunner/outproc/message.py

@@ -59,5 +59,7 @@ class OutProc(base.OutProc):
       not string.strip() or
       string.startswith("==") or
       string.startswith("**") or
-      string.startswith("ANDROID")
+      string.startswith("ANDROID") or
+      # Android linker warning.
+      string.startswith('WARNING: linker:')
     )