QArrayDataOps: don't use value-initialization

... but default-initialization instead.

This bug may have rendered the diverse Qt::Uninitialized ctors
we have in Qt containers ineffective.

Change-Id: I5a369fa8527f19b6f8cc1a9f36512f6a0058839a
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

src/corelib/tools/qarraydataops.h

@@ -145,7 +145,7 @@ struct QGenericArrayOps
 
         T *const begin = this->begin();
         do {
-            new (begin + this->size) T();
+            new (begin + this->size) T;
         } while (uint(++this->size) != newSize);
     }