VM: Reland Inline instance object hash code into object header on 64bit.

runtime/vm/intrinsifier_ia32.cc

Index: runtime/vm/intrinsifier_ia32.cc
diff --git a/runtime/vm/intrinsifier_ia32.cc b/runtime/vm/intrinsifier_ia32.cc
index 16d5209cef3d0d6a3396ef7951b617c9cd65c62f..d739d35adc0a427721892f144b4377d582dbc446 100644
--- a/runtime/vm/intrinsifier_ia32.cc
+++ b/runtime/vm/intrinsifier_ia32.cc
@@ -1890,6 +1890,16 @@ void Intrinsifier::StringBaseSubstringMatches(Assembler* assembler) {
 }
 
 
+void Intrinsifier::Object_getHash(Assembler* assembler) {
+  UNREACHABLE();
+}
+
+
+void Intrinsifier::Object_setHash(Assembler* assembler) {
+  UNREACHABLE();
+}
+
+
 void Intrinsifier::StringBaseCharAt(Assembler* assembler) {
   Label fall_through, try_two_byte_string;
   __ movl(EBX, Address(ESP, +1 * kWordSize));  // Index.