Make FastNewFunctionContextStub take slots parameter

src/crankshaft/mips64/lithium-codegen-mips64.cc

Index: src/crankshaft/mips64/lithium-codegen-mips64.cc
diff --git a/src/crankshaft/mips64/lithium-codegen-mips64.cc b/src/crankshaft/mips64/lithium-codegen-mips64.cc
index 2681fae262dbe64e14433063c671a565b177cf7b..f66ae1283097ceef17e30bb57d21db5ff3a13374 100644
--- a/src/crankshaft/mips64/lithium-codegen-mips64.cc
+++ b/src/crankshaft/mips64/lithium-codegen-mips64.cc
@@ -161,14 +161,12 @@ void LCodeGen::DoPrologue(LPrologue* instr) {
       __ Push(info()->scope()->GetScopeInfo(info()->isolate()));
       __ CallRuntime(Runtime::kNewScriptContext);
       deopt_mode = Safepoint::kLazyDeopt;
-    } else if (slots <= FastNewFunctionContextStub::kMaximumSlots) {
-      FastNewFunctionContextStub stub(isolate(), slots);
+    } else {
+      FastNewFunctionContextStub stub(isolate());
+      __ li(FastNewFunctionContextDescriptor::SlotsRegister(), Operand(slots));
       __ CallStub(&stub);
       // Result of FastNewFunctionContextStub is always in new space.
       need_write_barrier = false;
-    } else {
-      __ push(a1);
-      __ CallRuntime(Runtime::kNewFunctionContext);
     }
     RecordSafepoint(deopt_mode);