Enable python tests with testdata.

BUILD

@@ -534,7 +534,10 @@ py_proto_library(
 
 py_proto_library(
     name = "python_specific_test_protos",
-    srcs = glob(["python/google/protobuf/internal/*.proto"]),
+    srcs = glob([
+        "python/google/protobuf/internal/*.proto",
+        "python/google/protobuf/internal/import_test_package/*.proto",
+    ]),
     include = "python",
     protoc = ":protoc",
     deps = [":python_common_test_protos"],
@@ -552,6 +555,9 @@ py_library(
 
 internal_protobuf_py_tests(
     name = "python_tests_batch",
+    data = glob([
+        "src/google/protobuf/**/*",
+    ]),
     modules = [
         "descriptor_database_test",
         "descriptor_pool_test",
@@ -559,13 +565,13 @@ internal_protobuf_py_tests(
         "generator_test",
         "json_format_test",
         "message_factory_test",
-        # "message_test",      # failed due to testdata path
+        "message_test",
         "proto_builder_test",
-        # "reflection_test",   # failed due to testdata path
+        "reflection_test",
         "service_reflection_test",
         "symbol_database_test",
         "text_encoding_test",
-        # "text_format_test",  # failed due to testdata path
+        "text_format_test",
         "unknown_fields_test",
         "wire_format_test",
     ],