Minor streamlining of setCurrentValue

Author: cowtowncoder

src/main/java/com/fasterxml/jackson/core/base/GeneratorBase.java

@@ -136,7 +136,9 @@ public Object getCurrentValue() {
 
     @Override
     public void setCurrentValue(Object v) {
-        _writeContext.setCurrentValue(v);
+        if (_writeContext != null) {
+            _writeContext.setCurrentValue(v);
+        }
     }
 
     /*
@@ -291,7 +293,6 @@ public void writeStartObject(Object forValue) throws IOException
         if ((_writeContext != null) && (forValue != null)) {
             _writeContext.setCurrentValue(forValue);
         }
-        setCurrentValue(forValue);
     }
 
     /*

src/main/java/com/fasterxml/jackson/core/json/JsonWriteContext.java

@@ -29,9 +29,8 @@ public class JsonWriteContext extends JsonStreamContext
 
     /*
     /**********************************************************
-    /* Simple instance reuse slots; speed up things
-    /* a bit (10-15%) for docs with lots of small
-    /* arrays/objects
+    /* Simple instance reuse slots; speed up things a bit (10-15%)
+    /* for docs with lots of small arrays/objects
     /**********************************************************
      */