Make filegroup paths relative to module dir in mixed builds

filegroup.srcs must have a .rel() version of their paths
that is relative to the module directory. Previously in
mixed builds, the relative path wasn't filled in.

Bug: 229251008
Bug: 204244290
Test: go tests, and USE_BAZEL_ANALYSIS=1 m apexer with the following cl
Change-Id: I11a2a8b96139e0e7b956fa4c256a9a99c02f88f3

android/bazel_paths_test.go

@@ -0,0 +1,108 @@
+// Copyright 2022 Google Inc. All rights reserved.
+//
+// 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.
+
+package android
+
+import (
+	"path/filepath"
+	"testing"
+)
+
+type TestBazelPathContext struct{}
+
+func (*TestBazelPathContext) Config() Config {
+	cfg := NullConfig("out", "out/soong")
+	cfg.BazelContext = MockBazelContext{
+		OutputBaseDir: "out/bazel",
+	}
+	return cfg
+}
+
+func (*TestBazelPathContext) AddNinjaFileDeps(deps ...string) {
+	panic("Unimplemented")
+}
+
+func TestPathForBazelOut(t *testing.T) {
+	ctx := &TestBazelPathContext{}
+	out := PathForBazelOut(ctx, "foo/bar/baz/boq.txt")
+	expectedPath := filepath.Join(ctx.Config().BazelContext.OutputBase(), "execroot/__main__/foo/bar/baz/boq.txt")
+	if out.String() != expectedPath {
+		t.Errorf("incorrect OutputPath: expected %q, got %q", expectedPath, out.String())
+	}
+
+	expectedRelPath := "foo/bar/baz/boq.txt"
+	if out.Rel() != expectedRelPath {
+		t.Errorf("incorrect OutputPath.Rel(): expected %q, got %q", expectedRelPath, out.Rel())
+	}
+}
+
+func TestPathForBazelOutRelative(t *testing.T) {
+	ctx := &TestBazelPathContext{}
+	out := PathForBazelOutRelative(ctx, "foo/bar", "foo/bar/baz/boq.txt")
+
+	expectedPath := filepath.Join(ctx.Config().BazelContext.OutputBase(), "execroot/__main__/foo/bar/baz/boq.txt")
+	if out.String() != expectedPath {
+		t.Errorf("incorrect OutputPath: expected %q, got %q", expectedPath, out.String())
+	}
+
+	expectedRelPath := "baz/boq.txt"
+	if out.Rel() != expectedRelPath {
+		t.Errorf("incorrect OutputPath.Rel(): expected %q, got %q", expectedRelPath, out.Rel())
+	}
+}
+
+func TestPathForBazelOutRelativeUnderBinFolder(t *testing.T) {
+	ctx := &TestBazelPathContext{}
+	out := PathForBazelOutRelative(ctx, "foo/bar", "bazel-out/linux_x86_64-fastbuild-ST-b4ef1c4402f9/bin/foo/bar/baz/boq.txt")
+
+	expectedPath := filepath.Join(ctx.Config().BazelContext.OutputBase(), "execroot/__main__/bazel-out/linux_x86_64-fastbuild-ST-b4ef1c4402f9/bin/foo/bar/baz/boq.txt")
+	if out.String() != expectedPath {
+		t.Errorf("incorrect OutputPath: expected %q, got %q", expectedPath, out.String())
+	}
+
+	expectedRelPath := "baz/boq.txt"
+	if out.Rel() != expectedRelPath {
+		t.Errorf("incorrect OutputPath.Rel(): expected %q, got %q", expectedRelPath, out.Rel())
+	}
+}
+
+func TestPathForBazelOutOutsideOfExecroot(t *testing.T) {
+	ctx := &TestBazelPathContext{}
+	out := PathForBazelOut(ctx, "../bazel_tools/linux_x86_64-fastbuild/bin/tools/android/java_base_extras.jar")
+
+	expectedPath := filepath.Join(ctx.Config().BazelContext.OutputBase(), "execroot/bazel_tools/linux_x86_64-fastbuild/bin/tools/android/java_base_extras.jar")
+	if out.String() != expectedPath {
+		t.Errorf("incorrect OutputPath: expected %q, got %q", expectedPath, out.String())
+	}
+
+	expectedRelPath := "execroot/bazel_tools/linux_x86_64-fastbuild/bin/tools/android/java_base_extras.jar"
+	if out.Rel() != expectedRelPath {
+		t.Errorf("incorrect OutputPath.Rel(): expected %q, got %q", expectedRelPath, out.Rel())
+	}
+}
+
+func TestPathForBazelOutRelativeWithParentDirectoryRoot(t *testing.T) {
+	ctx := &TestBazelPathContext{}
+	out := PathForBazelOutRelative(ctx, "../bazel_tools", "../bazel_tools/foo/bar/baz.sh")
+
+	expectedPath := filepath.Join(ctx.Config().BazelContext.OutputBase(), "execroot/bazel_tools/foo/bar/baz.sh")
+	if out.String() != expectedPath {
+		t.Errorf("incorrect OutputPath: expected %q, got %q", expectedPath, out.String())
+	}
+
+	expectedRelPath := "foo/bar/baz.sh"
+	if out.Rel() != expectedRelPath {
+		t.Errorf("incorrect OutputPath.Rel(): expected %q, got %q", expectedRelPath, out.Rel())
+	}
+}