Precompilation: Don't look at embedder allocated pages when finalizing the VM isolate.

runtime/vm/pages.cc

Index: runtime/vm/pages.cc
diff --git a/runtime/vm/pages.cc b/runtime/vm/pages.cc
index 177b09159a0bcbe8839fffa65ec068345d7a0fd9..d7d3a2c5f43a8589b9b7cf06aac9c890d4f744bc 100644
--- a/runtime/vm/pages.cc
+++ b/runtime/vm/pages.cc
@@ -611,6 +611,15 @@ void PageSpace::VisitObjects(ObjectVisitor* visitor) const {
 }
 
 
+void PageSpace::VisitObjectsNoEmbedderPages(ObjectVisitor* visitor) const {
+  for (ExclusivePageIterator it(this); !it.Done(); it.Advance()) {
+    if (!it.page()->embedder_allocated()) {
+      it.page()->VisitObjects(visitor);
+    }
+  }
+}
+
+
 void PageSpace::VisitObjectPointers(ObjectPointerVisitor* visitor) const {
   for (ExclusivePageIterator it(this); !it.Done(); it.Advance()) {
     it.page()->VisitObjectPointers(visitor);
@@ -652,15 +661,13 @@ RawObject* PageSpace::FindObject(FindObjectVisitor* visitor,
 }
 
 
-void PageSpace::WriteProtect(bool read_only, bool include_code_pages) {
+void PageSpace::WriteProtect(bool read_only) {
   if (read_only) {
     // Avoid MakeIterable trying to write to the heap.
     AbandonBumpAllocation();
   }
   for (ExclusivePageIterator it(this); !it.Done(); it.Advance()) {
-    HeapPage::PageType page_type = it.page()->type();
-    if ((page_type != HeapPage::kReadOnlyData) &&
-        ((page_type != HeapPage::kExecutable) || include_code_pages)) {
+    if (!it.page()->embedder_allocated()) {
       it.page()->WriteProtect(read_only);
     }
   }