build: add v8_context_generator to mksnapshot zip (3-0-x) (#15505)

* build: add v8_context_generator to mksnapshot

Starting with 3-0-x, in order to use custom snapshots the v8_context_snapshot_generator binary is also needed.
Also, add tests for mksnapshot.

* Actually run verify-mksnapshot

script/verify-mksnapshot.py

@@ -0,0 +1,101 @@
+#!/usr/bin/env python
+
+import glob
+import os
+import shutil
+import subprocess
+import sys
+
+from lib.util import electron_gyp, rm_rf, scoped_cwd
+
+
+SOURCE_ROOT = os.path.abspath(os.path.dirname(os.path.dirname(__file__)))
+SNAPSHOT_DIR = os.path.join(SOURCE_ROOT, 'vendor', 'download',
+                                 'libchromiumcontent', 'static_library')
+PROJECT_NAME = electron_gyp()['project_name%']
+PRODUCT_NAME = electron_gyp()['product_name%']
+SNAPSHOT_SOURCE = os.path.join(SOURCE_ROOT, 'spec', 'fixtures', 'testsnap.js')
+
+def main():
+  os.chdir(SOURCE_ROOT)
+  app_path = create_app_copy()
+  blob_out_path = app_path
+  snapshot_gen_path =  os.path.join(SNAPSHOT_DIR, 'snapshot_gen', '*')
+  snapshot_gen_files = glob.glob(snapshot_gen_path)
+  if sys.platform == 'darwin':
+    electron = os.path.join(app_path, 'Contents', 'MacOS', PRODUCT_NAME)
+    blob_out_path = os.path.join(app_path, 'Contents', 'Frameworks',
+                    '{0} Framework.framework'.format(PROJECT_NAME),
+                    'Resources')
+    snapshot_gen_files += [ os.path.join(SNAPSHOT_DIR, 'libffmpeg.dylib') ]
+  elif sys.platform == 'win32':
+    electron = os.path.join(app_path, '{0}.exe'.format(PROJECT_NAME))
+    snapshot_gen_files += [
+      os.path.join(SNAPSHOT_DIR, 'ffmpeg.dll'),
+      os.path.join(SNAPSHOT_DIR, 'ffmpeg.dll.lib'),
+    ]
+  else:
+    electron = os.path.join(app_path, PROJECT_NAME)
+    snapshot_gen_files += [ os.path.join(SNAPSHOT_DIR, 'libffmpeg.so') ]
+
+  # Copy mksnapshot and friends to the directory the snapshot_blob should be
+  # generated in.
+  mksnapshot_binary = get_binary_path('mksnapshot', SNAPSHOT_DIR)
+  shutil.copy2(mksnapshot_binary, blob_out_path)
+  for gen_file in snapshot_gen_files:
+    shutil.copy2(gen_file, blob_out_path)
+
+  returncode = 0
+  try:
+    with scoped_cwd(blob_out_path):
+      mkargs = [ get_binary_path('mksnapshot', blob_out_path), \
+                 SNAPSHOT_SOURCE, '--startup_blob', 'snapshot_blob.bin' ]
+      subprocess.check_call(mkargs)
+      print 'ok mksnapshot successfully created snapshot_blob.bin.'
+      context_snapshot = 'v8_context_snapshot.bin'
+      context_snapshot_path = os.path.join(blob_out_path, context_snapshot)
+      gen_binary = get_binary_path('v8_context_snapshot_generator', \
+                                   blob_out_path)
+      genargs = [ gen_binary, \
+                 '--output_file={0}'.format(context_snapshot_path) ]
+      subprocess.check_call(genargs)
+      print 'ok v8_context_snapshot_generator successfully created ' \
+            + context_snapshot
+
+    test_path = os.path.join('spec', 'fixtures', 'snapshot-items-available.js')
+    subprocess.check_call([electron, test_path])
+    print 'ok successfully used custom snapshot.'
+  except subprocess.CalledProcessError as e:
+    print 'not ok an error was encountered while testing mksnapshot.'
+    print e
+    returncode = e.returncode
+  except KeyboardInterrupt:
+    print 'Other error'
+    returncode = 0
+
+  return returncode
+
+
+# Create copy of app to create custom snapshot
+def create_app_copy():
+  initial_app_path = os.path.join(SOURCE_ROOT, 'out', 'R')
+  app_path = os.path.join(SOURCE_ROOT, 'out', 'R-mksnapshot-test')
+
+  if sys.platform == 'darwin':
+    app_name = '{0}.app'.format(PRODUCT_NAME)
+    initial_app_path = os.path.join(initial_app_path, app_name)
+    app_path = os.path.join(app_path, app_name)
+
+  rm_rf(app_path)
+  shutil.copytree(initial_app_path, app_path, symlinks=True)
+  return app_path
+
+def get_binary_path(binary_name, root_path):
+  if sys.platform == 'win32':
+    binary_path = os.path.join(root_path, '{0}.exe'.format(binary_name))
+  else:
+    binary_path = os.path.join(root_path, binary_name)
+  return binary_path
+
+if __name__ == '__main__':
+  sys.exit(main())