Change DCHECK_IS_ON() to DCHECK_IS_ON

mojo/system/dispatcher.cc

Index: mojo/system/dispatcher.cc
diff --git a/mojo/system/dispatcher.cc b/mojo/system/dispatcher.cc
index 0e39d2c7c7fd8de6646eb497097edb8ccdd3990c..986c18d08ea0e37d6e2f70912571c477cd0c34c3 100644
--- a/mojo/system/dispatcher.cc
+++ b/mojo/system/dispatcher.cc
@@ -416,7 +416,7 @@ bool Dispatcher::SerializeAndClose(Channel* channel,
 
   // We have to call |GetMaximumSerializedSizeImplNoLock()| first, because we
   // leave it to |SerializeAndCloseImplNoLock()| to close the thing.
-  size_t max_size = DCHECK_IS_ON() ?
+  size_t max_size = DCHECK_IS_ON ?
       GetMaximumSerializedSizeImplNoLock(channel) : static_cast<size_t>(-1);
 
   // Like other |...Close()| methods, we mark ourselves as closed before calling