Add create_density_splits option to java_apk.gypi / android_apk (gn)

build/android/gyp/package_resources.py

Index: build/android/gyp/package_resources.py
diff --git a/build/android/gyp/package_resources.py b/build/android/gyp/package_resources.py
index 53937664c8b8de02e44bed4aba8fa29f3f3ddc25..a73d9d5831f13233b1608b7e028263613ea8d33d 100755
--- a/build/android/gyp/package_resources.py
+++ b/build/android/gyp/package_resources.py
@@ -16,9 +16,52 @@ https://android.googlesource.com/platform/sdk/+/master/files/ant/build.xml
 import optparse
 import os
 import shutil
+import zipfile
 
 from util import build_utils
 
+
+# List is generated from the chrome_apk.apk_intermediates.ap_ via:
+#     unzip -l $FILE_AP_ | cut -c31- | grep res/draw | cut -d'/' -f 2 | sort \
+#     | uniq | grep -- -tvdpi- | cut -c10-
+# and then manually sorted.
+# Note that we can't just do a cross-product of dimentions because the filenames
+# become too big and aapt fails to create the files.
+# This leaves all default drawables (mdpi) in the main apk. Android gets upset
+# though if any drawables are missing from the default drawables/ directory.
+DENSITY_SPLITS = {
+    'hdpi': (
+        'hdpi-v4', # Order matters for output file names.
+        'ldrtl-hdpi-v4',
+        'sw600dp-hdpi-v13',
+        'ldrtl-hdpi-v17',
+        'ldrtl-sw600dp-hdpi-v17',
+        'hdpi-v21',
+    ),
+    'xhdpi': (
+        'xhdpi-v4',
+        'ldrtl-xhdpi-v4',
+        'sw600dp-xhdpi-v13',
+        'ldrtl-xhdpi-v17',
+        'ldrtl-sw600dp-xhdpi-v17',
+        'xhdpi-v21',
+    ),
+    'xxhdpi': (
+        'xxhdpi-v4',
+        'ldrtl-xxhdpi-v4',
+        'sw600dp-xxhdpi-v13',
+        'ldrtl-xxhdpi-v17',
+        'ldrtl-sw600dp-xxhdpi-v17',
+        'xxhdpi-v21',
+    ),
+    'tvdpi': (
+        'tvdpi-v4',
+        'sw600dp-tvdpi-v13',
+        'ldrtl-sw600dp-tvdpi-v17',
+    ),
+}
+
+
 def ParseArgs():
   """Parses command line options.
 
@@ -48,6 +91,10 @@ def ParseArgs():
                     help='directories containing assets to be packaged')
   parser.add_option('--no-compress', help='disables compression for the '
                     'given comma separated list of extensions')
+  parser.add_option(
+      '--create-density-splits',
+      action='store_true',
+      help='Enables density splits')
 
   parser.add_option('--apk-path',
                     help='Path to output (partial) apk.')
@@ -114,6 +161,29 @@ def PackageArgsForExtractedZip(d):
   return package_command
 
 
+def RenameDensitySplits(apk_path):
+  """Renames all density splits to have shorter / predictable names."""
+  for density, config in DENSITY_SPLITS.iteritems():
+    src_path = '%s_%s' % (apk_path, '_'.join(config))
+    dst_path = '%s-%s' % (apk_path, density)
+    if os.path.exists(dst_path):
+      os.unlink(dst_path)
+    os.rename(src_path, dst_path)
+
+
+def CheckDensityMissedConfigs(apk_path):
+  """Raises an exception if apk_path contains any density-specifc files."""
+  triggers = ['-%s' % density for density in DENSITY_SPLITS]
+  with zipfile.ZipFile(apk_path) as main_apk_zip:
+    for name in main_apk_zip.namelist():
+      for trigger in triggers:
+        if trigger in name and not 'mipmap-' in name:
+          raise Exception(('Found density in main apk that should have been ' +
+                           'put into a split: %s\nYou need to update ' +
+                           'package_resources.py to include this new ' +
+                           'config.') % name)
+
+
 def main():
   options = ParseArgs()
   android_jar = os.path.join(options.android_sdk, 'android.jar')
@@ -128,7 +198,6 @@ def main():
                        '--no-crunch',
                        '-f',
                        '--auto-add-overlay',
-
                        '-I', android_jar,
                        '-F', options.apk_path,
                        '--ignore-assets', build_utils.AAPT_IGNORE_PATTERN,
@@ -152,12 +221,20 @@ def main():
         build_utils.ExtractAll(z, path=subdir)
         package_command += PackageArgsForExtractedZip(subdir)
 
+    if options.create_density_splits:
+      for config in DENSITY_SPLITS.itervalues():
+        package_command.extend(('--split', ','.join(config)))
+
     if 'Debug' in options.configuration_name:
       package_command += ['--debug-mode']
 
     build_utils.CheckOutput(
         package_command, print_stdout=False, print_stderr=False)
 
+    if options.create_density_splits:
+      CheckDensityMissedConfigs(options.apk_path)
+      RenameDensitySplits(options.apk_path)
+
     if options.depfile:
       build_utils.WriteDepfile(
           options.depfile,