Add enforcement of idmap policies

Teaches idmap2 to recognize policy restrictions put on overlayable
resources. If overlayable enforcement is turned on for an overlay, then
any resources defined within the overlayable api of the target will have
policy restrictions imposed on them. All resources without overlayable
definitions will continue to be overlayable without policy restrictions.

Bug: 119390857
Test: atest idmap2 and booting

Co-authored-by: Ryan Mitchell <rtmitchell@google.com>
Change-Id: I7e435648eb6e4a87b0b90a7b2a0c3f33c1516ea6
diff --git a/cmds/idmap2/tests/FileUtilsTests.cpp b/cmds/idmap2/tests/FileUtilsTests.cpp
index 4bf832a..d9d9a7f 100644
--- a/cmds/idmap2/tests/FileUtilsTests.cpp
+++ b/cmds/idmap2/tests/FileUtilsTests.cpp
@@ -37,10 +37,10 @@
                             [](unsigned char type ATTRIBUTE_UNUSED,
                                const std::string& path ATTRIBUTE_UNUSED) -> bool { return true; });
   ASSERT_THAT(v, NotNull());
-  ASSERT_EQ(v->size(), 4U);
-  ASSERT_EQ(
-      std::set<std::string>(v->begin(), v->end()),
-      std::set<std::string>({root + "/.", root + "/..", root + "/overlay", root + "/target"}));
+  ASSERT_EQ(v->size(), 6U);
+  ASSERT_EQ(std::set<std::string>(v->begin(), v->end()),
+            std::set<std::string>({root + "/.", root + "/..", root + "/overlay", root + "/target",
+                                   root + "/system-overlay", root + "/system-overlay-invalid"}));
 }
 
 TEST(FileUtilsTests, FindFilesFindApkFilesRecursive) {
@@ -49,11 +49,13 @@
     return type == DT_REG && path.size() > 4 && path.compare(path.size() - 4, 4, ".apk") == 0;
   });
   ASSERT_THAT(v, NotNull());
-  ASSERT_EQ(v->size(), 4U);
+  ASSERT_EQ(v->size(), 6U);
   ASSERT_EQ(std::set<std::string>(v->begin(), v->end()),
             std::set<std::string>({root + "/target/target.apk", root + "/overlay/overlay.apk",
                                    root + "/overlay/overlay-static-1.apk",
-                                   root + "/overlay/overlay-static-2.apk"}));
+                                   root + "/overlay/overlay-static-2.apk",
+                                   root + "/system-overlay/system-overlay.apk",
+                                   root + "/system-overlay-invalid/system-overlay-invalid.apk"}));
 }
 
 TEST(FileUtilsTests, ReadFile) {