Add a dummy testing/buildbot entry for the new win-asan bot.

TBR=dpranke

Bug: 869973
Change-Id: I768bbb4ae73c52d5fbd9d91960add069eefa5fac
Reviewed-on: https://chromium-review.googlesource.com/1164642Reviewed-by: Nico Weber <thakis@chromium.org>
Commit-Queue: Nico Weber <thakis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#581116}

testing/buildbot/chromium.memory.json

@@ -7117,5 +7117,10 @@
         "test": "wtf_unittests"
       }
     ]
+  },
+  "win-asan": {
+    "additional_compile_targets": [
+      "base_unittests"
+    ]
   }
 }

testing/buildbot/waterfalls.pyl

@@ -2980,6 +2980,12 @@
           'gtest_tests': 'chromium_mac_gtests',
         },
       },
+      'win-asan': {
+        # TODO(thakis): test_suites 'gtest_tests': 'chromium_win_gtests' instead
+        'additional_compile_targets': [
+          'base_unittests',
+        ],
+      },
     },
   },
   {