Reapply "Do not directly load smi constants larger than a 16 bit..."

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 6d89718d677290b9136ca04aa5629a987048e891..250dc170c137a25a73bfd9d568b37a7b70f7c05d 100644
--- a/runtime/vm/assembler_mips.h
+++ b/runtime/vm/assembler_mips.h
@@ -12,6 +12,7 @@
 #include "platform/assert.h"
 #include "platform/utils.h"
 #include "vm/constants_mips.h"
+#include "vm/object.h"
 #include "vm/simulator.h"
 
 // References to documentation in this file refer to:
@@ -1127,6 +1128,11 @@ class Assembler : public ValueObject {
   // up on entry (it is the frame of the unoptimized code).
   void EnterOsrFrame(intptr_t extra_size);
 
+  // On some other platforms, we draw a distinction between safe and unsafe
+  // smis.
+  static bool IsSafe(const Object& object) { return true; }
+  static bool IsSafeSmi(const Object& object) { return object.IsSmi(); }
+
  private:
   AssemblerBuffer buffer_;
   GrowableObjectArray& object_pool_;  // Objects and patchable jump targets.