Implemented CORS mechanism

[maifeeulasad]

closes #2015

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[maifeeulasad]

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[maifeeulasad]

When I ran the v8 in debug mode locally I had no issues. It passed. Here is the exact command.

ZIG_V8_VERSION=v0.4.4                                                            
V8_VERSION=14.0.365.4
OS=linux
ARCH=x86_64
CACHE_DIR=~/.cache

mkdir -p "$CACHE_DIR/v8" v8
wget -O "$CACHE_DIR/v8/libc_v8.a" \
  "https://github.com/lightpanda-io/zig-v8-fork/releases/download/${ZIG_V8_VERSION}/libc_v8_${V8_VERSION}_${OS}_${ARCH}_debug.a"
ln -sf "$CACHE_DIR/v8/libc_v8.a" v8/libc_v8_debug.a

zig build -Dprebuilt_v8_path=~/.cache/v8/libc_v8.a -Dtsan=true test

And regarding demo runner I am bit confused now! Care to guide me please? So that we can get this done!

cc: @krichprollsch

[krichprollsch]

@maifeeulasad no worries, we have flaky tests. I will re-start them, not a blocker for review.

[maifeeulasad]

@krichprollsch eagerly waiting for reviews and open for change requests.

[krichprollsch]

I may be wrong, but it seems only isReponseAllowed is used from Cors.zig, other functions are deadcode?

$ ag "Cors\." src/
src/browser/webapi/net/Fetch.zig
22:const Cors = @import("../../../network/Cors.zig");
211:        if (!Cors.isResponseAllowed(allow_origin, allow_credentials, requesting_origin.?, self._allow_credentials)) {

src/browser/webapi/net/XMLHttpRequest.zig
25:const Cors = @import("../../../network/Cors.zig");
508:        if (!Cors.isResponseAllowed(allow_origin, allow_credentials, request_origin.?, self._with_credentials)) {

[maifeeulasad]

Fixing this. Give me a week.