Revert "Convert build scripts to CMake (#13427)"

This reverts commit 354df17d16.

scripts/download-webkit.sh

@@ -0,0 +1,85 @@
+#!/usr/bin/env bash
+set -e
+
+OUTDIR="$1"
+TAG="$2"
+PKG="$3"
+
+if [ -z "$OUTDIR" ]; then
+  echo "Missing outdir"
+  exit 1
+fi
+if [ -z "$TAG" ]; then
+  echo "Missing tag"
+  exit 1
+fi
+if [ -z "$PKG" ]; then
+  echo "Missing package"
+  exit 1
+fi
+
+url="https://github.com/oven-sh/WebKit/releases/download/autobuild-$TAG/$PKG.tar.gz"
+
+old_tar_dir="$(dirname "$0")/../.webkit-cache"
+tar_dir="$(dirname "$0")/../.cache"
+if [ -d "$old_tar_dir" ]; then
+  # migration step from the old system
+  mkdir "$tar_dir"
+  mv "$old_tar_dir"/* "$tar_dir"
+  rm -r "$old_tar_dir"
+fi
+
+tar="$tar_dir/$PKG-$TAG.tar.gz"
+
+mkdir -p "$OUTDIR"
+mkdir -p "$tar_dir"
+
+if [ -f "$OUTDIR/.tag" ]; then
+  read_tag="$(cat "$OUTDIR/.tag")"
+  if [ "$read_tag" == "$TAG-$PKG" ]; then
+    exit 0
+  fi
+fi
+
+rm -rf "$OUTDIR"
+
+download () {
+  local command="$1"
+  local retries="$2"
+  local options="$-"
+  if [[ $options == *e* ]]; then
+    set +e
+  fi
+  $command
+  local exit_code=$?
+  if [[ $options == *e* ]]; then
+    set -e
+  fi
+  if [[ $exit_code -ne 0 && $retries -gt 0 ]]; then
+    download "$command" $(($retries - 1)) 
+  else
+    return $exit_code
+  fi
+}
+
+# this is a big download so we will retry 5 times and ask curl to resume
+# download from where failure occurred if it fails and is rerun
+if [ ! -f "$tar" ]; then
+  echo "-- Downloading WebKit"
+  if ! download "curl -C - --http1.1 -o $tar.tmp -L $url" 5; then
+    echo "Failed to download $url"
+    exit 1
+  else
+    mv $tar.tmp $tar
+  fi
+fi
+
+tar -xzf "$tar" -C "$(dirname "$OUTDIR")" || (rm "$tar" && exit 1)
+
+# We want to make sure we use the system-version of icucore on macOS
+if [ "$(uname)" == "Darwin" ]; then
+  # delete the unicode folder from include
+  rm -rf "$OUTDIR/include/unicode"
+fi
+
+echo "$TAG-$PKG" >"$OUTDIR/.tag"