Revert "Revert "Merge pull request #9543 from NixOS/staging.post-15.06""

This reverts commit 741bf840da.

This reverts the fallout from reverting the major changes.

pkgs/development/web/nodejs/no-xcode.patch

@@ -70,24 +70,3 @@ diff -Naur a/tools/gyp/pylib/gyp/xcode_emulation.py b/tools/gyp/pylib/gyp/xcode_
  
    def AdjustLibraries(self, libraries, config_name=None):
      """Transforms entries like 'Cocoa.framework' in libraries into entries like
-@@ -1018,12 +1033,16 @@
-     # Since the value returned by this function is only used when ARCHS is not
-     # set, then on iOS we return "i386", as the default xcode project generator
-     # does not set ARCHS if it is not set in the .gyp file.
--    if self.isIOS:
-+    
-+    try:
-+      if self.isIOS:
-+        return 'i386'
-+      version, build = self._XcodeVersion()
-+      if version >= '0500':
-+        return 'x86_64'
-       return 'i386'
--    version, build = self._XcodeVersion()
--    if version >= '0500':
-+    except:
-       return 'x86_64'
--    return 'i386'
- 
- class MacPrefixHeader(object):
-   """A class that helps with emulating Xcode's GCC_PREFIX_HEADER feature.