Add support for nodejs-mobile

Author: jaimecbernardo

lib/util/compile.js

@@ -10,13 +10,25 @@ const cp = require('child_process');
 
 // try to build up the complete path to node-gyp
 /* priority:
+  - node-gyp on ENV:NODEJS_MOBILE_GYP
   - node-gyp on ENV:npm_config_node_gyp (https://github.com/npm/npm/pull/4887)
   - node-gyp on NODE_PATH
   - node-gyp inside npm on NODE_PATH (ignore on iojs)
   - node-gyp inside npm beside node exe
 */
 function which_node_gyp() {
   let node_gyp_bin;
+  if (process.env.NODEJS_MOBILE_GYP) {
+    // nodejs-mobile was using npm_config_node_gyp, but that's currently being overwritten by npm 7+
+    try {
+      node_gyp_bin = process.env.NODEJS_MOBILE_GYP;
+      if (existsSync(node_gyp_bin)) {
+        return node_gyp_bin;
+      }
+    } catch (err) {
+      // do nothing
+    }
+  }
   if (process.env.npm_config_node_gyp) {
     try {
       node_gyp_bin = process.env.npm_config_node_gyp;