runtime.diff

diff --git a/core/src/main/java/org/jruby/ext/strscan/RubyStringScanner.java b/core/src/main/java/org/jruby/ext/strscan/RubyStringScanner.java
index 7b150c67ef..bc4453d355 100644
--- a/core/src/main/java/org/jruby/ext/strscan/RubyStringScanner.java
+++ b/core/src/main/java/org/jruby/ext/strscan/RubyStringScanner.java
@@ -246,7 +246,7 @@ public class RubyStringScanner extends RubyObject {
     };
 
     private IRubyObject scan(ThreadContext context, IRubyObject regex, boolean succptr, boolean getstr, boolean headonly) {
-        final Ruby runtime = getRuntime();
+        final Ruby runtime = context.runtime;
         if (!(regex instanceof RubyRegexp)) throw runtime.newTypeError("wrong argument type " + regex.getMetaClass() + " (expected Regexp)");
         check();
 
@@ -438,9 +438,12 @@ public class RubyStringScanner extends RubyObject {
     }
 
     @JRubyMethod(name = "unscan")
-    public IRubyObject unscan() {
+    public IRubyObject unscan(ThreadContext context) {
+        return unscan(context.runtime);
+    }
+
+    private IRubyObject unscan(Ruby runtime) {
         check();
-        Ruby runtime = getRuntime();
 
         if (!isMatched()) {
             RubyClass errorClass = runtime.getClass("StringScanner").getClass("Error");
@@ -451,6 +454,11 @@ public class RubyStringScanner extends RubyObject {
         return this;
     }
 
+    @Deprecated
+    public IRubyObject unscan() {
+        return unscan(getRuntime());
+    }
+
     @JRubyMethod(name = "beginning_of_line?", alias = "bol?")
     public IRubyObject bol_p() {
         check();