filegroup.path is used to specify the include path for aidl files

filegroup {
    name: "foo",
    srcs: ["srcs/aidl/com/android/**/*.aidl"],
    path: "srcs/aidl",
}

cc_library { // or java_library, etc.
    name: "bar",
    srcs: [":foo"],
}

automatically adds "-Ipath/to/foo/srcs/aidl" when compiling the aidl
files from foo for bar. This allows us to omit aidl include path
when using sources in other places via file group.

Bug: 135922046
Test: m (unit tests added)
Change-Id: I9b42f316f2858fb6da72c2f58a314f391416e809
diff --git a/cc/testing.go b/cc/testing.go
index bf806bc..f0ad33b 100644
--- a/cc/testing.go
+++ b/cc/testing.go
@@ -265,6 +265,7 @@
 		"bar.c":       nil,
 		"a.proto":     nil,
 		"b.aidl":      nil,
+		"sub/c.aidl":  nil,
 		"my_include":  nil,
 		"foo.map.txt": nil,
 		"liba.so":     nil,