Use case-sensitive regular expressions in --no-compress-regex

On some windows versions (plus wine) std::regex has issues with the
icase flag (making regex case insensitive). Put the responsibility of
the case sensitivity on the caller.

Fixes: 127793905
Test: wine aapt2_tests.exe -> Util_test
Change-Id: I6775514d3ef43c2c47465bf39ceaf2c195909724
diff --git a/tools/aapt2/cmd/Util.cpp b/tools/aapt2/cmd/Util.cpp
index e2c65ba7..7214f1a 100644
--- a/tools/aapt2/cmd/Util.cpp
+++ b/tools/aapt2/cmd/Util.cpp
@@ -436,9 +436,9 @@
 }
 
 std::regex GetRegularExpression(const std::string &input) {
-  // Standard ECMAScript grammar plus case insensitive.
+  // Standard ECMAScript grammar.
   std::regex case_insensitive(
-      input, std::regex_constants::icase | std::regex_constants::ECMAScript);
+      input, std::regex_constants::ECMAScript);
   return case_insensitive;
 }