Generate sdk snapshots for the R build

This change replicates the behavior of the generate_ml_bundle.sh that
creates an Android.bp file along with the necessary file structure for
an R build.

It adds the information needed to a ForRBuild object which is set on
those MainlineModules that need to provide SDKs for R. That includes
a list of SdkLibrary objects each of which has a name and a flag that
indicates whether it is a shared library.

The R BuildRelease creator function builds the sdk snapshots as normal
and then extracts information from those snapshot files to construct
snapshots suitable for an R build. It then passes the directory
containing those new snapshot files to populate_dist() which will then
copy them into the correct location in the dist directory.

For each MainlineModule that provides an SDK for R the following is
created in the out/soong/mainline-sdks/for-R-build directory:
* A sub-directory using the apex name containing:
 * An Android.bp file with definitions for each SdkLibrary.
 * A file structure containing API txt file, removed API txt file,
   a srcjar containing the stub sources and a stubs jar.
* A zip file containing the contents of the previous directory whose
  name is <sdk-name>-current.zip, to match the files that are
  generated by Soong when building sdk snapshots.

As R does not support the Soong config boilerplate code that
transformation is disabled for R.

Test: atest --host mainline_modules_sdks_test
      packages/modules/common/build/mainline_modules_sdks.sh
      pyformat -s 4 --force_quote_type double -i build/mainline_modules_sdks*.py
      /usr/bin/pylint --rcfile $ANDROID_BUILD_TOP/tools/repohooks/tools/pylintrc build/mainline_modules_sdks*.py
Change-Id: I70001782496a3e9805bf56181c0e08419e31e191

build/mainline_modules_sdks_test_data/google_wifi_for_r_Android.bp

@@ -0,0 +1,49 @@
+// DO NOT EDIT. Auto-generated by the following:
+//     path/to/mainline_modules_sdks.sh
+//
+// 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.
+//
+
+java_sdk_library_import {
+    name: "framework-wifi",
+    owner: "google",
+    prefer: true,
+    shared_library: false,
+    apex_available: [
+        "com.android.wifi",
+        "test_com.android.wifi",
+    ],
+    public: {
+        jars: ["sdk_library/public/framework-wifi-stubs.jar"],
+        stub_srcs: ["sdk_library/public/framework-wifi.srcjar"],
+        current_api: "sdk_library/public/framework-wifi.txt",
+        removed_api: "sdk_library/public/framework-wifi-removed.txt",
+        sdk_version: "module_current",
+    },
+    system: {
+        jars: ["sdk_library/system/framework-wifi-stubs.jar"],
+        stub_srcs: ["sdk_library/system/framework-wifi.srcjar"],
+        current_api: "sdk_library/system/framework-wifi.txt",
+        removed_api: "sdk_library/system/framework-wifi-removed.txt",
+        sdk_version: "module_current",
+    },
+    module_lib: {
+        jars: ["sdk_library/module-lib/framework-wifi-stubs.jar"],
+        stub_srcs: ["sdk_library/module-lib/framework-wifi.srcjar"],
+        current_api: "sdk_library/module-lib/framework-wifi.txt",
+        removed_api: "sdk_library/module-lib/framework-wifi-removed.txt",
+        sdk_version: "module_current",
+    },
+}

build/mainline_modules_sdks_test_data/ipsec_for_r_Android.bp

@@ -0,0 +1,49 @@
+// DO NOT EDIT. Auto-generated by the following:
+//     path/to/mainline_modules_sdks.sh
+//
+// 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.
+//
+
+java_sdk_library_import {
+    name: "android.net.ipsec.ike",
+    owner: "google",
+    prefer: true,
+    shared_library: true,
+    apex_available: [
+        "com.android.ipsec",
+        "test_com.android.ipsec",
+    ],
+    public: {
+        jars: ["sdk_library/public/android.net.ipsec.ike-stubs.jar"],
+        stub_srcs: ["sdk_library/public/android.net.ipsec.ike.srcjar"],
+        current_api: "sdk_library/public/android.net.ipsec.ike.txt",
+        removed_api: "sdk_library/public/android.net.ipsec.ike-removed.txt",
+        sdk_version: "module_current",
+    },
+    system: {
+        jars: ["sdk_library/system/android.net.ipsec.ike-stubs.jar"],
+        stub_srcs: ["sdk_library/system/android.net.ipsec.ike.srcjar"],
+        current_api: "sdk_library/system/android.net.ipsec.ike.txt",
+        removed_api: "sdk_library/system/android.net.ipsec.ike-removed.txt",
+        sdk_version: "module_current",
+    },
+    module_lib: {
+        jars: ["sdk_library/module-lib/android.net.ipsec.ike-stubs.jar"],
+        stub_srcs: ["sdk_library/module-lib/android.net.ipsec.ike.srcjar"],
+        current_api: "sdk_library/module-lib/android.net.ipsec.ike.txt",
+        removed_api: "sdk_library/module-lib/android.net.ipsec.ike-removed.txt",
+        sdk_version: "module_current",
+    },
+}