[crankshaft] Fix deoptimization loop w/ non-monomorphic arguments access.

src/crankshaft/hydrogen.cc

Index: src/crankshaft/hydrogen.cc
diff --git a/src/crankshaft/hydrogen.cc b/src/crankshaft/hydrogen.cc
index 2e0695dfdf8b4902ef1366226b0f9c5282403036..4cdf74782e26fe4743be78491bcb9840e34b8ad1 100644
--- a/src/crankshaft/hydrogen.cc
+++ b/src/crankshaft/hydrogen.cc
@@ -7452,6 +7452,9 @@ bool HOptimizedGraphBuilder::TryArgumentsAccess(Property* expr) {
       result = New<HConstant>(argument_count);
     }
   } else {
+    // We need to take into account the KEYED_LOAD_IC feedback to guard the
+    // HBoundsCheck instructions below.
+    if (!expr->IsMonomorphic()) return false;
     CHECK_ALIVE_OR_RETURN(VisitForValue(expr->obj(), ARGUMENTS_ALLOWED), true);
     CHECK_ALIVE_OR_RETURN(VisitForValue(expr->key()), true);
     HValue* key = Pop();