Merge pull request #8843 from jakesmith/hpcc-15822

HPCC-15822 Uninitialized member preventing spilling

Reviewed-By: Richard Chapman <rchapman@hpccsystems.com>

thorlcr/thorutil/thmem.cpp

@@ -1237,6 +1237,8 @@ CThorSpillableRowArray::CThorSpillableRowArray(CActivityBase &activity)
     : CThorExpandingRowArray(activity)
 {
     initCommon();
+    commitDelta = CommitStep;
+    throwOnOom = false;
 }
 
 CThorSpillableRowArray::CThorSpillableRowArray(CActivityBase &activity, IThorRowInterfaces *rowIf, bool allowNulls, StableSortFlag stableSort, rowidx_t initialSize, size32_t _commitDelta)