Desktop: Add build-client-if-desktop

package.json

@@ -174,7 +174,7 @@
     "autoprefixer": "postcss -r --use autoprefixer",
     "postcss": "postcss -r -u postcss-custom-properties -u autoprefixer -c postcss.config.json",
     "prebuild": "npm run -s install-if-deps-outdated",
-    "build": "run-p -s build-devdocs:* build-server build-client-if-prod build-css",
+    "build": "run-p -s build-devdocs:* build-server build-client-if-prod build-client-if-desktop build-css",
     "build-css": "run-p -s build-css:*",
     "build-css:debug": "node-sass --include-path client --source-map \"public/style-debug.css.map\" assets/stylesheets/style.scss public/style-debug.css && npm run -s autoprefixer -- public/style-debug.css",
     "build-css:directly": "node-sass --include-path client assets/stylesheets/directly.scss public/directly.css && npm run -s autoprefixer -- public/directly.css",
@@ -196,6 +196,7 @@
     "build-server": "npm run -s env -- webpack --display-error-details --config webpack.config.node.js",
     "build-client": "npm run -s env -- webpack --display-error-details --config webpack.config.js",
     "build-client-if-prod": "node -e \"process.env.CALYPSO_ENV === 'production' && process.exit(1)\" || ( npm run build-client && npm run minify )",
+    "build-client-if-desktop": "node -e \"process.env.CALYPSO_ENV === 'desktop' && process.exit(1)\" || ( npm run build-client && npm run minify )",
     "clean": "npm run -s clean:build && npm run -s clean:devdocs && npm run -s clean:public",
     "clean:build": "npm run -s rm -- build && npm run -s rm -- server/bundler .json && npm run -s rm -- .babel-cache",
     "clean:devdocs": "npm run -s rm -- server/devdocs/search-index.js && npm run -s rm -- server/devdocs/proptypes-index.json && npm run -s rm -- server/devdocs/components-usage-stats.json",