Issue 4720 - enable devenv target for Edge packager

build.py

 # This Source Code Form is subject to the terms of the Mozilla Public
 # License, v. 2.0. If a copy of the MPL was not distributed with this
 # file, You can obtain one at http://mozilla.org/MPL/2.0/.
 
 import os
 import sys
 import re
 import subprocess
 import shutil
 from getopt import getopt, GetoptError
@@ skipping 179 matching lines @@
 
     if type in {'chrome', 'gecko'}:
         import buildtools.packagerChrome as packager
     elif type == 'edge':
         import buildtools.packagerEdge as packager
 
     packager.createBuild(baseDir, type=type, **kwargs)
 
 
 def createDevEnv(baseDir, scriptName, opts, args, type):
-    import buildtools.packagerChrome as packager
+    if type == 'edge':
+        import buildtools.packagerEdge as packager
+    else:
+        import buildtools.packagerChrome as packager
 
     file = StringIO()
     packager.createBuild(baseDir, type=type, outFile=file, devenv=True, releaseBuild=True)
 
     from buildtools.packager import getDevEnvPath
     devenv_dir = getDevEnvPath(baseDir, type)
 
     shutil.rmtree(devenv_dir, ignore_errors=True)
 
     file.seek(0)
@@ skipping 176 matching lines @@
     command.description = 'Creates an extension build with given file name. If output_file is missing a default name will be chosen.'
     command.params = '[options] [output_file]'
     command.addOption('Use given build number (if omitted the build number will be retrieved from Mercurial)', short='b', long='build', value='num')
     command.addOption('File containing private key and certificates required to sign the package', short='k', long='key', value='file', types={'chrome'})
     command.addOption('Create a release build', short='r', long='release')
     command.supportedTypes = {'gecko', 'chrome', 'edge'}
 
 with addCommand(createDevEnv, 'devenv') as command:
     command.shortDescription = 'Set up a development environment'
     command.description = 'Will set up or update the devenv folder as an unpacked extension folder for development.'
-    command.supportedTypes = {'gecko', 'chrome'}
+    command.supportedTypes = {'gecko', 'chrome', 'edge'}
 
 with addCommand(setupTranslations, 'setuptrans') as command:
     command.shortDescription = 'Sets up translation languages'
     command.description = 'Sets up translation languages for the project on crowdin.net.'
     command.params = '[options] project-key'
 
 with addCommand(updateTranslationMaster, 'translate') as command:
     command.shortDescription = 'Updates translation master files'
     command.description = 'Updates the translation master files in the project on crowdin.net.'
     command.params = '[options] project-key'
@@ skipping 95 matching lines @@
                 if option in {'-h', '--help'}:
                     usage(scriptName, type, command)
                     sys.exit()
             commands[command](baseDir, scriptName, opts, args, type)
         else:
             print 'Command %s is not supported for this application type' % command
             usage(scriptName, type)
     else:
         print 'Command %s is unrecognized' % command
         usage(scriptName, type)