Raise an exception if a unittest target is missing.

build/android/run_tests.py

Index: build/android/run_tests.py
diff --git a/build/android/run_tests.py b/build/android/run_tests.py
index 15186026629e4e22ca5d3bcd6defc79e2f061751..2818dfe07106f35802063e623e705a94741af3b1 100755
--- a/build/android/run_tests.py
+++ b/build/android/run_tests.py
@@ -113,11 +113,10 @@ def FullyQualifiedTestSuites(exe, option_test_suite, build_type):
                              for t in all_test_suites]
   for t, q in zip(all_test_suites, qualified_test_suites):
     if not os.path.exists(q):
-      logging.critical('Test suite %s not found in %s.\n'
-                       'Supported test suites:\n %s\n'
-                       'Ensure it has been built.\n',
-                       t, q, _TEST_SUITES)
-      return []
+      raise Exception('Test suite %s not found in %s.\n'
+                      'Supported test suites:\n %s\n'
+                      'Ensure it has been built.\n' %
+                      (t, q, _TEST_SUITES))
   return qualified_test_suites