Make FastNewFunctionContextStub take slots parameter

src/crankshaft/arm64/lithium-codegen-arm64.cc

Index: src/crankshaft/arm64/lithium-codegen-arm64.cc
diff --git a/src/crankshaft/arm64/lithium-codegen-arm64.cc b/src/crankshaft/arm64/lithium-codegen-arm64.cc
index 4cc34aaa48dcadd97757dd1a8d60e9fc0d16ad28..a80afcefecc4ee1c6606868688197ce70578b222 100644
--- a/src/crankshaft/arm64/lithium-codegen-arm64.cc
+++ b/src/crankshaft/arm64/lithium-codegen-arm64.cc
@@ -594,14 +594,12 @@ void LCodeGen::DoPrologue(LPrologue* instr) {
       __ Push(x1, x10);
       __ CallRuntime(Runtime::kNewScriptContext);
       deopt_mode = Safepoint::kLazyDeopt;
-    } else if (slots <= FastNewFunctionContextStub::kMaximumSlots) {
-      FastNewFunctionContextStub stub(isolate(), slots);
+    } else {
+      FastNewFunctionContextStub stub(isolate());
+      __ Mov(FastNewFunctionContextDescriptor::SlotsRegister(), slots);
       __ CallStub(&stub);
       // Result of FastNewFunctionContextStub is always in new space.
       need_write_barrier = false;
-    } else {
-      __ Push(x1);
-      __ CallRuntime(Runtime::kNewFunctionContext);
     }
     RecordSafepoint(deopt_mode);
     // Context is returned in x0. It replaces the context passed to us. It's