Reimplement Maps and Sets in JS

src/mips/code-stubs-mips.cc

Index: src/mips/code-stubs-mips.cc
diff --git a/src/mips/code-stubs-mips.cc b/src/mips/code-stubs-mips.cc
index 8a9ee3d70cb7cca4fb4dae9c57efbee6b37d5224..1a6d5e1535c6d1cf629a685aa5d2cd55b350f5f0 100644
--- a/src/mips/code-stubs-mips.cc
+++ b/src/mips/code-stubs-mips.cc
@@ -1159,16 +1159,6 @@ void CEntryStub::Generate(MacroAssembler* masm) {
   }
 
 
-  // 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;
-    __ LoadRoot(t0, Heap::kTheHoleValueRootIndex);
-    __ Branch(&okay, ne, v0, Operand(t0));
-    __ stop("The hole escaped");
-    __ bind(&okay);
-  }
-
   // Check result for exception sentinel.
   Label exception_returned;
   __ LoadRoot(t0, Heap::kExceptionRootIndex);