Revert of Revert of X87: Reimplement Maps and Sets in JS

src/x87/code-stubs-x87.cc

Index: src/x87/code-stubs-x87.cc
diff --git a/src/x87/code-stubs-x87.cc b/src/x87/code-stubs-x87.cc
index e0c8f3d7b5a1f9961391fb3ee5bfef6ff93a7e89..2cd2e7ba46ff19bbdb4847317a09d91f4495895d 100644
--- a/src/x87/code-stubs-x87.cc
+++ b/src/x87/code-stubs-x87.cc
@@ -2186,16 +2186,6 @@
   __ call(ebx);
   // Result is in eax or edx:eax - do not destroy these registers!
 
-  // Runtime functions should not return 'the hole'.  Allowing it to escape may
-  // lead to crashes in the IC code later.
-  if (FLAG_debug_code) {
-    Label okay;
-    __ cmp(eax, isolate()->factory()->the_hole_value());
-    __ j(not_equal, &okay, Label::kNear);
-    __ int3();
-    __ bind(&okay);
-  }
-
   // Check result for exception sentinel.
   Label exception_returned;
   __ cmp(eax, isolate()->factory()->exception());