Rework the core of class parsing/runtime semantic (#3598)

Changes:
 - Use the pre-scanner to provide information for the parser about the existence of the class constructor
 - The allocation of the super declarative environment is no longer needed
 - The VM frame context holds the information about the this binding status
 - Reduce the number of class related VM/CBC instructions
 - Improve ecma_op_function_{construct, call} to properly set new.target

JerryScript-DCO-1.0-Signed-off-by: Robert Fancsik frobert@inf.u-szeged.hu

jerry-core/lit/lit-magic-strings.h

@@ -50,6 +50,7 @@ typedef enum
   LIT_INTERNAL_MAGIC_STRING_MAP_KEY, /**< Property key used when an object is a key in a map object */
   LIT_INTERNAL_MAGIC_API_INTERNAL, /**< Property key used to add non-visible JS properties from the public API  */
   LIT_INTERNAL_MAGIC_STRING_ARRAY_PROTOTYPE_VALUES, /**< %ArrayProto_values% intrinsic routine */
+  LIT_INTERNAL_MAGIC_THIS_BINDING_VALUE, /**< FunctionEnvironmentRecord [[ThisBindingValue]] internal slot */
   /* List of well known symbols */
   LIT_GLOBAL_SYMBOL_HAS_INSTANCE, /**< @@hasInstance well known symbol */
   LIT_GLOBAL_SYMBOL_IS_CONCAT_SPREADABLE, /**< @@isConcatSpreadable well known symbol */
@@ -70,7 +71,6 @@ typedef enum
   LIT_INTERNAL_MAGIC_STRING_NATIVE_POINTER, /**< native pointer info associated with an object */
   LIT_FIRST_INTERNAL_MAGIC_STRING = LIT_INTERNAL_MAGIC_STRING_NATIVE_POINTER,  /**< first index of internal
                                                                                 *   magic strings */
-  LIT_INTERNAL_MAGIC_STRING_CLASS_THIS_BINDING, /**< the this binding of the class constructor */
   LIT_INTERNAL_MAGIC_STRING_WEAK_REFS, /**< Weak references to the current object */
   LIT_INTERNAL_MAGIC_STRING_CONTAINER, /**< Literal ID for internal container objects */
   LIT_INTERNAL_MAGIC_STRING_INTERNAL_OBJECT, /**< Internal object ID for internal properties */