Added "unimplemented" syntax errors

[Razican]

This removes the panics in for...in parsing. It will still fail, but at least we don't bring the process down. This comes from the idea that "every panic is a bug", not just an unimplemented feature.

[github-actions]

Test262 conformance changes:

Test result	master count	PR count	difference
Total	78,413	78,415	+2
Passed	18,189	18,220	+31
Ignored	15,507	15,507	0
Failed	44,717	44,688	-29
Panics	13,519	12,480	-1,039
Conformance	23.20	23.24	+0.04%

[codecov]

Codecov Report

Merging #901 into master will decrease coverage by 0.05%.
The diff coverage is 0.00%.

@@            Coverage Diff             @@
##           master     #901      +/-   ##
==========================================
- Coverage   59.44%   59.39%   -0.06%     
==========================================
  Files         166      166              
  Lines       10474    10483       +9     
==========================================
  Hits         6226     6226              
- Misses       4248     4257       +9     

Impacted Files	Coverage Δ
boa/src/syntax/parser/error.rs	38.23% <0.00%> (-3.71%)	⬇️
...syntax/parser/statement/iteration/for_statement.rs	80.43% <0.00%> (-5.62%)	⬇️

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[HalidOdat]

Looks good to me! :)

[github-actions]

Benchmark for e112dbf

Click to view benchmark

Test	PR Benchmark	Master Benchmark	%
Arithmetic operations (Execution)	363.0±9.09ns	385.7±12.12ns	-5.89%
Arithmetic operations (Full)	262.7±9.66µs	263.0±11.67µs	-0.11%
Array access (Execution)	8.6±0.24µs	8.6±0.30µs	0.00%
Array access (Full)	282.7±10.72µs	259.1±14.97µs	+9.11%
Array creation (Execution)	2.7±0.08ms	2.7±0.10ms	0.00%
Array creation (Full)	3.1±0.12ms	2.7±0.12ms	+14.81%
Array pop (Execution)	1011.6±34.69µs	1000.7±51.89µs	+1.09%
Array pop (Full)	1517.2±53.34µs	1351.8±41.36µs	+12.24%
Boolean Object Access (Execution)	4.8±0.16µs	4.9±0.20µs	-2.04%
Boolean Object Access (Full)	272.9±18.52µs	288.7±9.80µs	-5.47%
Clean js (Execution)	730.8±31.14µs	733.4±33.04µs	-0.35%
Clean js (Full)	1055.5±32.22µs	1041.9±46.57µs	+1.31%
Clean js (Parser)	39.1±1.62µs	41.4±1.18µs	-5.56%
Create Realm	472.1±15.91ns	469.5±12.21ns	+0.55%
Dynamic Object Property Access (Execution)	6.0±0.20µs	6.2±0.24µs	-3.23%
Dynamic Object Property Access (Full)	282.8±14.35µs	272.5±15.08µs	+3.78%
Expression (Parser)	7.2±0.20µs	7.1±0.25µs	+1.41%
Fibonacci (Execution)	950.0±26.62µs	945.5±30.05µs	+0.48%
Fibonacci (Full)	1251.2±39.35µs	1138.5±47.38µs	+9.90%
For loop (Execution)	24.3±0.73µs	24.8±0.82µs	-2.02%
For loop (Full)	301.9±13.85µs	274.0±9.98µs	+10.18%
For loop (Parser)	19.1±0.75µs	19.2±0.72µs	-0.52%
Goal Symbols (Parser)	12.8±0.38µs	13.0±0.72µs	-1.54%
Hello World (Parser)	3.5±0.10µs	3.3±0.14µs	+6.06%
Long file (Parser)	806.2±20.04ns	813.1±25.67ns	-0.85%
Mini js (Execution)	649.8±15.38µs	611.4±33.41µs	+6.28%
Mini js (Full)	950.0±24.21µs	912.0±38.57µs	+4.17%
Mini js (Parser)	33.6±0.84µs	35.8±1.50µs	-6.15%
Number Object Access (Execution)	3.8±0.11µs	3.9±0.17µs	-2.56%
Number Object Access (Full)	272.7±8.61µs	279.2±9.13µs	-2.33%
Object Creation (Execution)	5.3±0.32µs	5.3±0.21µs	0.00%
Object Creation (Full)	271.5±8.90µs	257.8±10.68µs	+5.31%
RegExp (Execution)	10.0±0.34µs	9.9±0.46µs	+1.01%
RegExp (Full)	282.6±6.22µs	272.3±13.07µs	+3.78%
RegExp Literal (Execution)	11.0±0.34µs	11.3±0.57µs	-2.65%
RegExp Literal (Full)	292.6±11.43µs	288.4±11.20µs	+1.46%
RegExp Literal Creation (Execution)	10.3±0.37µs	9.7±0.38µs	+6.19%
RegExp Literal Creation (Full)	280.7±8.60µs	269.6±11.28µs	+4.12%
Static Object Property Access (Execution)	5.6±0.48µs	5.6±0.18µs	0.00%
Static Object Property Access (Full)	276.3±9.67µs	278.6±24.88µs	-0.83%
String Object Access (Execution)	7.4±0.26µs	7.5±0.51µs	-1.33%
String Object Access (Full)	292.6±10.35µs	262.4±10.03µs	+11.51%
String comparison (Execution)	6.9±0.28µs	7.0±0.28µs	-1.43%
String comparison (Full)	280.8±6.73µs	289.9±8.87µs	-3.14%
String concatenation (Execution)	5.6±0.24µs	5.6±0.19µs	0.00%
String concatenation (Full)	272.1±7.73µs	280.4±12.14µs	-2.96%
String copy (Execution)	4.4±0.13µs	4.4±0.11µs	0.00%
String copy (Full)	271.4±7.39µs	273.4±14.28µs	-0.73%
Symbols (Execution)	3.9±0.13µs	3.8±0.13µs	+2.63%
Symbols (Full)	261.2±8.83µs	244.2±10.22µs	+6.96%

[github-actions]

Benchmark for b4f08a1

Click to view benchmark

Test	PR Benchmark	Master Benchmark	%
Arithmetic operations (Execution)	376.8±17.35ns	391.0±13.48ns	-3.63%
Arithmetic operations (Full)	263.8±12.04µs	266.3±11.98µs	-0.94%
Array access (Execution)	8.8±0.42µs	8.8±0.34µs	0.00%
Array access (Full)	293.5±11.81µs	296.6±10.22µs	-1.05%
Array creation (Execution)	2.8±0.10ms	2.8±0.09ms	0.00%
Array creation (Full)	3.1±0.09ms	3.1±0.15ms	0.00%
Array pop (Execution)	987.6±65.67µs	1015.6±37.64µs	-2.76%
Array pop (Full)	1532.3±127.25µs	1527.8±56.58µs	+0.29%
Boolean Object Access (Execution)	5.0±0.17µs	4.9±0.27µs	+2.04%
Boolean Object Access (Full)	281.6±6.78µs	281.0±7.11µs	+0.21%
Clean js (Execution)	759.7±29.52µs	745.3±21.94µs	+1.93%
Clean js (Full)	1101.2±29.20µs	1081.8±36.82µs	+1.79%
Clean js (Parser)	40.4±2.00µs	38.9±1.96µs	+3.86%
Create Realm	480.2±27.23ns	498.0±25.37ns	-3.57%
Dynamic Object Property Access (Execution)	6.3±0.17µs	6.1±0.34µs	+3.28%
Dynamic Object Property Access (Full)	295.9±8.07µs	286.8±11.53µs	+3.17%
Expression (Parser)	7.5±0.42µs	7.4±0.16µs	+1.35%
Fibonacci (Execution)	992.4±28.49µs	984.2±32.03µs	+0.83%
Fibonacci (Full)	1323.7±47.36µs	1245.0±44.69µs	+6.32%
For loop (Execution)	25.0±1.08µs	25.2±0.92µs	-0.79%
For loop (Full)	312.0±12.47µs	310.9±10.13µs	+0.35%
For loop (Parser)	19.7±0.60µs	19.7±0.81µs	0.00%
Goal Symbols (Parser)	12.8±0.45µs	13.1±0.54µs	-2.29%
Hello World (Parser)	3.5±0.12µs	3.6±0.11µs	-2.78%
Long file (Parser)	836.6±28.84ns	819.6±29.73ns	+2.07%
Mini js (Execution)	679.6±23.99µs	677.2±34.42µs	+0.35%
Mini js (Full)	959.4±41.71µs	958.8±28.56µs	+0.06%
Mini js (Parser)	34.7±1.07µs	33.7±1.46µs	+2.97%
Number Object Access (Execution)	4.1±0.31µs	3.9±0.16µs	+5.13%
Number Object Access (Full)	283.0±6.98µs	279.1±10.36µs	+1.40%
Object Creation (Execution)	5.2±0.24µs	5.5±0.25µs	-5.45%
Object Creation (Full)	277.9±9.77µs	282.9±17.73µs	-1.77%
RegExp (Execution)	9.9±0.42µs	9.8±0.40µs	+1.02%
RegExp (Full)	294.1±12.51µs	289.0±11.44µs	+1.76%
RegExp Literal (Execution)	11.4±0.52µs	11.1±0.52µs	+2.70%
RegExp Literal (Full)	291.8±11.40µs	297.0±10.19µs	-1.75%
RegExp Literal Creation (Execution)	10.2±0.46µs	10.0±0.54µs	+2.00%
RegExp Literal Creation (Full)	289.5±8.62µs	288.1±8.87µs	+0.49%
Static Object Property Access (Execution)	5.6±0.21µs	5.7±0.29µs	-1.75%
Static Object Property Access (Full)	284.2±15.25µs	285.7±12.81µs	-0.53%
String Object Access (Execution)	7.5±0.32µs	7.8±0.38µs	-3.85%
String Object Access (Full)	286.4±9.13µs	283.6±8.59µs	+0.99%
String comparison (Execution)	7.1±0.19µs	7.1±0.21µs	0.00%
String comparison (Full)	292.2±8.73µs	288.7±10.27µs	+1.21%
String concatenation (Execution)	5.6±0.32µs	5.8±0.26µs	-3.45%
String concatenation (Full)	280.3±8.11µs	275.5±11.65µs	+1.74%
String copy (Execution)	4.6±0.20µs	4.4±0.19µs	+4.55%
String copy (Full)	275.2±15.33µs	280.3±9.08µs	-1.82%
Symbols (Execution)	4.0±0.28µs	4.0±0.15µs	0.00%
Symbols (Full)	272.6±11.59µs	271.9±9.76µs	+0.26%