Start removing the double-negative !ASSERT_DISABLED

Source/platform/graphics/Canvas2DLayerBridge.cpp

Index: Source/platform/graphics/Canvas2DLayerBridge.cpp
diff --git a/Source/platform/graphics/Canvas2DLayerBridge.cpp b/Source/platform/graphics/Canvas2DLayerBridge.cpp
index 9e190d946e312264b390f19b7f2797a975f50ab2..6aaf9d0bfd36e60ec4cd89eebf51cea88b434d43 100644
--- a/Source/platform/graphics/Canvas2DLayerBridge.cpp
+++ b/Source/platform/graphics/Canvas2DLayerBridge.cpp
@@ -118,7 +118,7 @@ Canvas2DLayerBridge::~Canvas2DLayerBridge()
     ASSERT(m_destructionInProgress);
     m_layer.clear();
     freeReleasedMailbox();
-#if !ASSERT_DISABLED
+#if ASSERT_ENABLED
     Vector<MailboxInfo>::iterator mailboxInfo;
     for (mailboxInfo = m_mailboxes.begin(); mailboxInfo < m_mailboxes.end(); ++mailboxInfo) {
         ASSERT(mailboxInfo->m_status != MailboxInUse);