AAPT2: allow regexes for extensions to not compress

Change-Id: I09d2ad1d1466643ca7628c6480224e16b9002ee5
Fixes: 67575899
Test: added + manual
diff --git a/tools/aapt2/cmd/Util_test.cpp b/tools/aapt2/cmd/Util_test.cpp
index f92f1e3..7e49261 100644
--- a/tools/aapt2/cmd/Util_test.cpp
+++ b/tools/aapt2/cmd/Util_test.cpp
@@ -383,4 +383,12 @@
   EXPECT_NE(*adjusted_contraints[1].configs.begin(), ConfigDescription::DefaultConfig());
 }
 
+TEST(UtilTest, RegularExperssions) {
+  std::string valid(".bc$");
+  std::regex expression = GetRegularExpression(valid);
+  EXPECT_TRUE(std::regex_search("file.abc", expression));
+  EXPECT_TRUE(std::regex_search("file.123bc", expression));
+  EXPECT_FALSE(std::regex_search("abc.zip", expression));
+}
+
 }  // namespace aapt