Get NDK python script tests running.

Imports weren't working in tests because the package had been created.
The Python "binaries" built by Soong don't seem to take their own
pkg_path into account, so I split the separate pieces of code here out
into their own packages.

Note that the ndk_api_coverage_parser tests do not actually pass
before or after this change (seems like it might be a
non-deterministic ordering issue in the attributes of the generated
output?), but they can at least be run now.

Test: pytest ndkstubgen
Test: pytest symbolfile
Test: pytest ndk_api_coverage_parser
Test: out/host/linux-x86/nativetest64/test_ndkstubgen/test_ndkstubgen
Test: out/host/linux-x86/nativetest64/test_symbolfile/test_symbolfile
Test: out/host/linux-x86/nativetest64/test_ndk_api_coverage_parser/test_ndk_api_coverage_parser
Bug: None
Change-Id: I2ac22f7ced7566e4808070f2f72fd04355846e0b

cc/ndk_api_coverage_parser/Android.bp

@@ -0,0 +1,46 @@
+//
+// Copyright (C) 2020 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+python_library_host {
+    name: "ndk_api_coverage_parser_lib",
+    pkg_path: "ndk_api_coverage_parser",
+    srcs: [
+        "__init__.py",
+    ],
+}
+
+python_test_host {
+    name: "test_ndk_api_coverage_parser",
+    main: "test_ndk_api_coverage_parser.py",
+    srcs: [
+        "test_ndk_api_coverage_parser.py",
+    ],
+    libs: [
+        "ndk_api_coverage_parser_lib",
+        "symbolfile",
+    ],
+}
+
+python_binary_host {
+    name: "ndk_api_coverage_parser",
+    main: "__init__.py",
+    srcs: [
+        "__init__.py",
+    ],
+    libs: [
+        "symbolfile",
+    ],
+}