Revert "js_runtime: streamline stringReplaceAllUnchecked"

tests/corelib/string_replace_all_test.dart

Index: tests/corelib/string_replace_all_test.dart
diff --git a/tests/corelib/string_replace_all_test.dart b/tests/corelib/string_replace_all_test.dart
index f63a9f7dc80c3e0e17ff02fe1b887e3ed4861d03..299d56ac99aae03506127d8348e4298788256736 100644
--- a/tests/corelib/string_replace_all_test.dart
+++ b/tests/corelib/string_replace_all_test.dart
@@ -46,16 +46,6 @@ testReplaceAll() {
 
   // Test replacing the empty string.
   Expect.equals("toAtoBtoCto", "ABC".replaceAll("", "to"));
-
-  // Pattern strings containing RegExp metacharacters - these are not
-  // interpreted as RegExps.
-  Expect.equals(r"$$", "||".replaceAll("|", r"$"));
-  Expect.equals(r"$$$$", "||".replaceAll("|", r"$$"));
-  Expect.equals(r"x$|x", "x|.|x".replaceAll("|.", r"$"));
-  Expect.equals(r"$$", "..".replaceAll(".", r"$"));
-  Expect.equals(r"[$$$$]", "[..]".replaceAll(".", r"$$"));
-  Expect.equals(r"[$]", "[..]".replaceAll("..", r"$"));
-  Expect.equals(r"$$", r"\\".replaceAll(r"\", r"$"));
 }
 
 testReplaceAllMapped() {