Make adb_install_apk.py saner for humans.

build/android/adb_install_apk.py

Index: build/android/adb_install_apk.py
diff --git a/build/android/adb_install_apk.py b/build/android/adb_install_apk.py
index a91510137925e766cf5166768f78679e7ed51c12..7a781eee62a0c0027a73a12f1a10be15c4fbf937 100755
--- a/build/android/adb_install_apk.py
+++ b/build/android/adb_install_apk.py
@@ -19,7 +19,7 @@ from pylib.utils import apk_helper
 def AddInstallAPKOption(option_parser):
   """Adds apk option used to install the APK to the OptionParser."""
   option_parser.add_option('--apk',
-                           help=('The name of the apk containing the '
+                           help=('DEPRECATED The name of the apk containing the'

[Nico, 2015/07/23 17:14:15]

I happened to look at this file today and see this DEPRECATED. Putting
DEPRECATED in help strings is not an effective deprecation strategy: I never saw
this, and I've been using this flag for a while now – it's what's recommended on
https://www.chromium.org/developers/how-tos/android-build-instructions etc. Even
now that I happened to see this, I don't know what to do instead so I can't
change the docs.

Since the flag works fine and is the documented way to go abou tings, maybe we
can just remove the DEPRECATED here? What's the motivation? (If it's to get rid
of the implicit dependency of "out", that's a good motivation, in that case
there could be a "use X instead" note here)

[jbudorick, 2015/07/23 17:28:49]

I believe there are multiple reasons for doing this:
 - removing the flag itself for a required single argument, as mentioned in the
description
 - more braodly, moving people and bots from the crazy automagical mode:

    # what will this install? who knows?
    ./build/android/adb_install_apk.py --apk ChromePublic

  to the more explicit, less magical mode:

    # much more clear
    ./build/android/adb_install_apk.py out/Release/apks/ChromePublic.apk

I would prefer updating the docs to calling this option un-deprecated, and will
do so.

                                  ' application (with the .apk extension).'))
   option_parser.add_option('--apk_package',
                            help=('The package name used by the apk containing '
@@ -40,10 +40,17 @@ def AddInstallAPKOption(option_parser):
                            'Default is env var BUILDTYPE or Debug.')
 
 
-def ValidateInstallAPKOption(option_parser, options):
+def ValidateInstallAPKOption(option_parser, options, args):
   """Validates the apk option and potentially qualifies the path."""
   if not options.apk:
-    option_parser.error('--apk is mandatory.')
+    if len(args) > 1:
+      options.apk = args[1]
+    else:
+      option_parser.error('apk target not specified.')
+
+  if not options.apk.endswith('.apk'):
+    options.apk += '.apk'
+
   if not os.path.exists(options.apk):
     options.apk = os.path.join(constants.GetOutDirectory(), 'apks',
                                options.apk)
@@ -51,12 +58,17 @@ def ValidateInstallAPKOption(option_parser, options):
 
 def main(argv):
   parser = optparse.OptionParser()
+  parser.set_usage("usage: %prog [options] target")
   AddInstallAPKOption(parser)
   options, args = parser.parse_args(argv)
+
+  if len(args) > 1 and options.apk:
+    parser.error("Appending the apk as argument can't be used with --apk.")
+  elif len(args) > 2:
+    parser.error("Too many arguments.")
+
   constants.SetBuildType(options.build_type)
-  ValidateInstallAPKOption(parser, options)
-  if len(args) > 1:
-    raise Exception('Error: Unknown argument:', args[1:])
+  ValidateInstallAPKOption(parser, options, args)
 
   devices = android_commands.GetAttachedDevices()
   if not devices: