Fix dart2js replace to escape all dollar characters in the replacement string.

sdk/lib/_internal/lib/string_helper.dart

Index: sdk/lib/_internal/lib/string_helper.dart
diff --git a/sdk/lib/_internal/lib/string_helper.dart b/sdk/lib/_internal/lib/string_helper.dart
index 328cf2909184940127157ee6929976bd67efed7e..e3fb93b40470279eb685584a98d8114f5d36849b 100644
--- a/sdk/lib/_internal/lib/string_helper.dart
+++ b/sdk/lib/_internal/lib/string_helper.dart
@@ -73,7 +73,7 @@ stringReplaceJS(receiver, replacer, to) {
   // The JavaScript String.replace method recognizes replacement
   // patterns in the replacement string. Dart does not have that
   // behavior.
-  to = JS('String', r'#.replace("$", "$$$$")', to);
+  to = JS('String', r'#.replace(/\$/g, "$$$$")', to);
   return JS('String', r'#.replace(#, #)', receiver, replacer, to);
 }