build: [ci] add GN linux CI build

.circleci/config.yml

@@ -313,6 +313,84 @@ jobs:
       xcode: "8.3.3"
     <<: *build-steps
 
+  electron-linux-gn:
+    environment:
+      DISPLAY: ':99.0'
+    docker:
+      - image: electronbuilds/electron:0.0.8
+    resource_class: 2xlarge
+    steps:
+      - run:
+          name: Setup depot tools
+          command: |
+            git clone --depth=1 https://chromium.googlesource.com/chromium/tools/depot_tools.git
+            echo 'export PATH=$PATH:`pwd`/depot_tools' >> $BASH_ENV
+      - checkout:
+          path: src/electron
+      - restore_cache:
+          paths:
+            - ~/.gclient-cache
+          keys:
+            - v1-gclient-cache-{{ checksum "src/electron/DEPS" }}
+            - v1-gclient-cache-
+      - run:
+          name: Gclient sync
+          command: |
+            echo $PATH
+            gclient config \
+              --name "src/electron" \
+              --unmanaged \
+              --cache-dir "$HOME/.gclient-cache" \
+              "$CIRCLE_REPOSITORY_URL"
+
+            gclient sync --with_branch_heads --with_tags
+      - save_cache:
+          paths:
+            - ~/.gclient-cache
+          key: v1-gclient-cache-{{ checksum "src/electron/DEPS" }}
+      - run:
+          name: GN gen
+          command: |
+            cd src
+            echo 'export CHROMIUM_BUILDTOOLS_PATH=`pwd`/buildtools' >> $BASH_ENV
+            source $BASH_ENV
+            mkdir out/Default
+            cat > out/Default/args.gn <<-EOF
+            root_extra_deps = [ "//electron" ]
+            is_electron_build = true
+            is_component_build = true
+            use_jumbo_build = true
+            v8_promise_internal_field_count = 1
+            v8_typed_array_max_size_in_heap = 0
+            EOF
+            gn gen out/Default
+      - run:
+          name: Ninja build
+          command: |
+            cd src
+            ninja -C out/Default electron:electron_app
+      - run:
+          name: Setup for headless testing
+          command: |
+            sh -e /etc/init.d/xvfb start
+      - run:
+          name: Test
+          environment:
+            MOCHA_REPORTER: mocha-junit-reporter
+            MOCHA_FILE: junit/test-results.xml
+            ELECTRON_DISABLE_SECURITY_WARNINGS: 1
+          command: |
+            cd src
+            ninja -C out/Default electron/build/node:headers
+            export npm_config_nodedir="$PWD/out/Default/gen/node_headers"
+            (cd electron/spec && npm install)
+            ./out/Default/electron electron/spec --ci --enable-logging
+      - store_test_results:
+          path: src/junit
+      - store_artifacts:
+          path: src/junit
+      - <<: *notify-slack-failure
+      - <<: *notify-slack-success
 
 workflows:
   version: 2
@@ -340,6 +418,9 @@ workflows:
   build-mas-x64:
     jobs:
       - electron-mas-x64
+  build-gn-linux:
+    jobs:
+      - electron-linux-gn
 
   nightly-release-test:
     triggers: