Reland debug output for landmines

TBR=jochen@chromium.org

Review URL: https://codereview.chromium.org/450873003

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@23011 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

tools/run-tests.py

@@ -267,6 +267,14 @@ def ProcessOptions(options):
     # Buildbots run presubmit tests as a separate step.
     options.no_presubmit = True
     options.no_network = True
+
+    # FIXME(machenbach): Temporary hack to debug landmines on buildbot.
+    # Hardcoded for make/ninja.
+    src_dir = os.path.dirname(os.path.dirname(os.path.realpath(__file__)))
+    target_dir  = options.mode[0] if options.mode else 'Release'
+    out_dir = os.path.join(src_dir, 'out', target_dir, '.landmines')
+    if os.path.exists(out_dir):
+      print "[INFO] Landmines tracker exists."
   if options.command_prefix:
     print("Specifying --command-prefix disables network distribution, "
           "running tests locally.")