Write protect executable pages in the VM.

runtime/vm/assembler_mips.h

Index: runtime/vm/assembler_mips.h
diff --git a/runtime/vm/assembler_mips.h b/runtime/vm/assembler_mips.h
index d17f05d9c7591c086e624cc3fa550a406afdf735..ccf7a5e24da78ea59a353d3387cd2b97c4f7dd6f 100644
--- a/runtime/vm/assembler_mips.h
+++ b/runtime/vm/assembler_mips.h
@@ -163,6 +163,13 @@ class Assembler : public ValueObject {
   // Misc. functionality
   intptr_t CodeSize() const { return buffer_.Size(); }
   intptr_t prologue_offset() const { return prologue_offset_; }
+
+  // Count the fixups that produce a pointer offset, without processing
+  // the fixups.
+  intptr_t CountPointerOffsets() const {
+    return buffer_.CountPointerOffsets();
+  }
+
   const ZoneGrowableArray<intptr_t>& GetPointerOffsets() const {
     return buffer_.pointer_offsets();
   }