Import 'regex' package vesion 1.3.6

* Add OWNERS
* No Android.bp yet
Bug: 152884384
Test: make

Change-Id: I455caf7833b6c437c1c133bc7b2f47b83da9cbce
diff --git a/tests/flags.rs b/tests/flags.rs
new file mode 100644
index 0000000..c33b82d
--- /dev/null
+++ b/tests/flags.rs
@@ -0,0 +1,31 @@
+mat!(match_flag_case, "(?-u)(?i)abc", "ABC", Some((0, 3)));
+mat!(match_flag_weird_case, "(?-u)(?i)a(?-i)bc", "Abc", Some((0, 3)));
+mat!(match_flag_weird_case_not, "(?-u)(?i)a(?-i)bc", "ABC", None);
+mat!(match_flag_case_dotnl, "(?-u)(?is)a(?u:.)", "A\n", Some((0, 2)));
+mat!(
+    match_flag_case_dotnl_toggle,
+    "(?-u)(?is)a(?u:.)(?-is)a(?u:.)",
+    "A\nab",
+    Some((0, 4))
+);
+mat!(
+    match_flag_case_dotnl_toggle_not,
+    "(?-u)(?is)a(?u:.)(?-is)a(?u:.)",
+    "A\na\n",
+    None
+);
+mat!(
+    match_flag_case_dotnl_toggle_ok,
+    "(?-u)(?is)a(?u:.)(?-is:a(?u:.))?",
+    "A\na\n",
+    Some((0, 2))
+);
+mat!(
+    match_flag_multi,
+    r"(?-u)(?m)(?:^\d+$\n?)+",
+    "123\n456\n789",
+    Some((0, 11))
+);
+mat!(match_flag_ungreedy, "(?U)a+", "aa", Some((0, 1)));
+mat!(match_flag_ungreedy_greedy, "(?U)a+?", "aa", Some((0, 2)));
+mat!(match_flag_ungreedy_noop, "(?U)(?-U)a+", "aa", Some((0, 2)));