Allow lexically declared "arguments" in function scope in sloppy mode.

test/cctest/interpreter/bytecode_expectations/CallLookupSlot.golden

 #
 # Autogenerated by generate-bytecode-expectations.
 #
 
 ---
 pool type: mixed
 execute: yes
 wrap: yes
 
 ---
 snippet: "
   g = function(){}; eval(''); return g();
 "
 frame size: 10
 parameter count: 1
 bytecode array length: 86
 bytecodes: [
                 B(CreateFunctionContext), U8(3),
                 B(PushContext), R(0),
                 B(Ldar), R(this),
                 B(StaContextSlot), R(context), U8(4),
                 B(CreateMappedArguments),
+                B(StaContextSlot), R(context), U8(6),
+                B(Ldar), R(new_target),
                 B(StaContextSlot), R(context), U8(5),
-                B(Ldar), R(new_target),
-                B(StaContextSlot), R(context), U8(6),
   /*   30 E> */ B(StackCheck),
   /*   34 S> */ B(CreateClosure), U8(0), U8(2),
   /*   36 E> */ B(StaLookupSlotSloppy), U8(1),
   /*   52 S> */ B(LdaConstant), U8(2),
                 B(Star), R(3),
                 B(CallRuntimeForPair), U16(Runtime::kLoadLookupSlotForCall), R(3), U8(1), R(1),
                 B(LdaConstant), U8(3),
                 B(Star), R(3),
                 B(LdaZero),
                 B(Star), R(7),
@@ skipping 15 matching lines @@
 ]
 constant pool: [
   InstanceType::SHARED_FUNCTION_INFO_TYPE,
   InstanceType::ONE_BYTE_INTERNALIZED_STRING_TYPE,
   InstanceType::ONE_BYTE_INTERNALIZED_STRING_TYPE,
   InstanceType::ONE_BYTE_INTERNALIZED_STRING_TYPE,
 ]
 handlers: [
 ]