Fix negative gtest filters for instrumentation tests.

build/android/pylib/instrumentation/instrumentation_test_instance.py

Index: build/android/pylib/instrumentation/instrumentation_test_instance.py
diff --git a/build/android/pylib/instrumentation/instrumentation_test_instance.py b/build/android/pylib/instrumentation/instrumentation_test_instance.py
index c11fd5fc546d598a3b356ffa7b1e418fc91916e7..8bfe4b3f30dfc9bd0bdd1ec0f52872b8afdaa3c7 100644
--- a/build/android/pylib/instrumentation/instrumentation_test_instance.py
+++ b/build/android/pylib/instrumentation/instrumentation_test_instance.py
@@ -235,7 +235,15 @@ def FilterTests(tests, test_filter=None, annotations=None,
       GetTestName(unqualified_class_test, sep='.'),
       GetUniqueTestName(t, sep='.')
     ]
-    return unittest_util.FilterTestNames(names, test_filter)
+
+    pattern_groups = test_filter.split('-')
+    if len(pattern_groups) > 1:
+      negative_filter = pattern_groups[1]
+      if unittest_util.FilterTestNames(names, negative_filter):
+        return []
+
+    positive_filter = pattern_groups[0]
+    return unittest_util.FilterTestNames(names, positive_filter)
 
   def annotation_filter(all_annotations):
     if not annotations: