[interpreter] Bytecode register optimizer.

test/cctest/interpreter/bytecode_expectations/WithStatement.golden

 #
 # Autogenerated by generate-bytecode-expectations.
 #
 
 ---
 pool type: mixed
 execute: yes
 wrap: yes
 
 ---
 snippet: "
   with ({x:42}) { return x; }
 "
 frame size: 4
 parameter count: 1
-bytecode array length: 26
+bytecode array length: 25
 bytecodes: [
   /*   30 E> */ B(StackCheck),
   /*   34 S> */ B(CreateObjectLiteral), U8(0), U8(0), U8(1),
                 B(Star), R(1),
                 B(ToObject),
                 B(Star), R(2),
-                B(Ldar), R(closure),
-                B(Star), R(3),
+                B(Mov), R(closure), R(3),
                 B(CallRuntime), U16(Runtime::kPushWithContext), R(2), U8(2),
                 B(PushContext), R(0),
   /*   50 S> */ B(LdaLookupSlot), U8(1),
                 B(PopContext), R(0),
   /*   62 S> */ B(Return),
 ]
 constant pool: [
   InstanceType::FIXED_ARRAY_TYPE,
   InstanceType::ONE_BYTE_INTERNALIZED_STRING_TYPE,
 ]
 handlers: [
 ]