Fail sooner and with better error message when attempting precompilation on IA32.

runtime/vm/megamorphic_cache_table.cc

Index: runtime/vm/megamorphic_cache_table.cc
diff --git a/runtime/vm/megamorphic_cache_table.cc b/runtime/vm/megamorphic_cache_table.cc
index 154d0e05be34e413dcdbce5ea55d401866af0890..84694db8e729510b11f3cb785b51f2d3f09e7698 100644
--- a/runtime/vm/megamorphic_cache_table.cc
+++ b/runtime/vm/megamorphic_cache_table.cc
@@ -22,7 +22,7 @@ RawMegamorphicCache* MegamorphicCacheTable::Lookup(Isolate* isolate,
   GrowableObjectArray& table = GrowableObjectArray::Handle(
       isolate->object_store()->megamorphic_cache_table());
   if (table.IsNull()) {
-    table = GrowableObjectArray::New();
+    table = GrowableObjectArray::New(Heap::kOld);
     ASSERT((table.Length() % kEntrySize) == 0);
     isolate->object_store()->set_megamorphic_cache_table(table);
   } else {
@@ -36,9 +36,9 @@ RawMegamorphicCache* MegamorphicCacheTable::Lookup(Isolate* isolate,
 
   const MegamorphicCache& cache =
       MegamorphicCache::Handle(MegamorphicCache::New());
-  table.Add(name);
-  table.Add(descriptor);
-  table.Add(cache);
+  table.Add(name, Heap::kOld);
+  table.Add(descriptor, Heap::kOld);
+  table.Add(cache, Heap::kOld);
   ASSERT((table.Length() % kEntrySize) == 0);
   return cache.raw();
 }