Bug 1674302 Part 1 - Change a FLEX_LOG to dump address of flex item's frame rather than flex item itself. r=emilio

All the other FLEX_LOGs dump the address of flex item's frame.

Differential Revision: https://phabricator.services.mozilla.com/D104644

layout/generic/nsFlexContainerFrame.cpp

@@ -3201,8 +3201,8 @@ void FlexLine::ResolveFlexibleLengths(nscoord aFlexContainerMainSize,
             availableFreeSpace -= sizeDelta;
 
             item.SetMainSize(item.MainSize() + sizeDelta);
-            FLEX_LOG("  child %p receives %d, for a total of %d", &item,
+            FLEX_LOG("  flex item %p receives %d, for a total of %d",
-                     sizeDelta, item.MainSize());
+                     item.Frame(), sizeDelta, item.MainSize());
           }
         }