Extract signature_trie.py from verify_overlaps.py

Makes the efficient pattern matching of hidden API flags that is used
by verify_overlaps.py available for use in other scripts.

As part of the move this cleans up the python to use consistent quotes,
and fix pylint issues.

Bug: 202154151
Test: m out/soong/hiddenapi/hiddenapi-flags.csv
      atest --host signature_trie_test verify_overlaps_test
      pyformat -s 4 --force_quote_type double -i scripts/hiddenapi/signature_trie*
      /usr/bin/pylint --rcfile $ANDROID_BUILD_TOP/tools/repohooks/tools/pylintrc scripts/hiddenapi/signature_trie*
Change-Id: I758ca70bb5b7e6806f14b72fd04f821a069f188f

Change-Id: I73fdb7e02127a8c0171a285221d9e6024310953d

scripts/hiddenapi/Android.bp

@@ -69,10 +69,37 @@ python_test_host {
     },
 }
 
+python_library_host {
+    name: "signature_trie",
+    srcs: ["signature_trie.py"],
+}
+
+python_test_host {
+    name: "signature_trie_test",
+    main: "signature_trie_test.py",
+    srcs: ["signature_trie_test.py"],
+    libs: ["signature_trie"],
+    version: {
+        py2: {
+            enabled: false,
+        },
+        py3: {
+            enabled: true,
+            embedded_launcher: true,
+        },
+    },
+    test_options: {
+        unit_test: true,
+    },
+}
+
 python_binary_host {
     name: "verify_overlaps",
     main: "verify_overlaps.py",
     srcs: ["verify_overlaps.py"],
+    libs: [
+        "signature_trie",
+    ],
     version: {
         py2: {
             enabled: false,
@@ -91,6 +118,9 @@ python_test_host {
         "verify_overlaps.py",
         "verify_overlaps_test.py",
     ],
+    libs: [
+        "signature_trie",
+    ],
     version: {
         py2: {
             enabled: false,