package/Distribution: always require CLT.

We always require it in `install.sh` and we need it for all but the
latest version of macOS so this seems a simpler compromise.

Fixes Homebrew#15802

package/Distribution.xml

@@ -31,13 +31,13 @@
  </allowed-os-versions>
 
  <script>
+ // See https://developer.apple.com/documentation/installer_js
  function installation_check() {
- if (system.files.fileExistsAtPath("/Library/Developer/CommandLineTools/usr/bin/git") ||
- system.files.fileExistsAtPath("/Applications/Xcode.app/Contents/Developer/usr/bin/git")) {
+ if (system.files.fileExistsAtPath("/Library/Developer/CommandLineTools/usr/bin/git")) {
  return true;
  } else {
- my.result.title = "Xcode Command Line Tools (CLT) are missing";
- my.result.message = "You must install the Xcode Command Line Tools (CLT) or Xcode before installing Homebrew. Install the CLT by running `xcode-select --install` from a Terminal.";
+ my.result.title = "Command Line Tools (CLT) are missing";
+ my.result.message = "You must install the Command Line Tools (CLT) before installing Homebrew by running `xcode-select --install` from a Terminal.";
  my.result.type = "Fatal";
  return false;
  }