Escape mapped names before applying them. (#721)

Author: alcatrazEscapee

src/common/java/net/minecraftforge/gradle/common/util/McpNames.java

@@ -197,8 +197,10 @@ private String getMapped(String srg) {
     private String replaceInLine(String line) {
         StringBuffer buf = new StringBuffer();
         Matcher matcher = SRG_FINDER.matcher(line);
-        while (matcher.find())
-            matcher.appendReplacement(buf, getMapped(matcher.group()));
+        while (matcher.find()) {
+            // Since '$' is a valid character in identifiers, but we need to NOT treat this as a regex group, escape any occurrences
+            matcher.appendReplacement(buf, Matcher.quoteReplacement(getMapped(matcher.group())));
+        }
         matcher.appendTail(buf);
         return buf.toString();
     }