Add a snapshot of flutter/engine/src/build to our sdk

build/android/gyp/util/proguard_util.py

Index: build/android/gyp/util/proguard_util.py
diff --git a/build/android/gyp/util/proguard_util.py b/build/android/gyp/util/proguard_util.py
new file mode 100644
index 0000000000000000000000000000000000000000..901cd9f2a8f30c5491986492cc3a4575776ef8a2
--- /dev/null
+++ b/build/android/gyp/util/proguard_util.py
@@ -0,0 +1,128 @@
+# Copyright 2015 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+import os
+from util import build_utils
+
+def FilterProguardOutput(output):
+  '''ProGuard outputs boring stuff to stdout (proguard version, jar path, etc)
+  as well as interesting stuff (notes, warnings, etc). If stdout is entirely
+  boring, this method suppresses the output.
+  '''
+  ignore_patterns = [
+    'ProGuard, version ',
+    'Reading program jar [',
+    'Reading library jar [',
+    'Preparing output jar [',
+    '  Copying resources from program jar [',
+  ]
+  for line in output.splitlines():
+    for pattern in ignore_patterns:
+      if line.startswith(pattern):
+        break
+    else:
+      # line doesn't match any of the patterns; it's probably something worth
+      # printing out.
+      return output
+  return ''
+
+
+class ProguardCmdBuilder(object):
+  def __init__(self, proguard_jar):
+    assert os.path.exists(proguard_jar)
+    self._proguard_jar_path = proguard_jar
+    self._test = None
+    self._mapping = None
+    self._libraries = None
+    self._injars = None
+    self._configs = None
+    self._outjar = None
+
+  def outjar(self, path):
+    assert self._outjar is None
+    self._outjar = path
+
+  def is_test(self, enable):
+    assert self._test is None
+    self._test = enable
+
+  def mapping(self, path):
+    assert self._mapping is None
+    assert os.path.exists(path), path
+    self._mapping = path
+
+  def libraryjars(self, paths):
+    assert self._libraries is None
+    for p in paths:
+      assert os.path.exists(p), p
+    self._libraries = paths
+
+  def injars(self, paths):
+    assert self._injars is None
+    for p in paths:
+      assert os.path.exists(p), p
+    self._injars = paths
+
+  def configs(self, paths):
+    assert self._configs is None
+    for p in paths:
+      assert os.path.exists(p), p
+    self._configs = paths
+
+  def build(self):
+    assert self._injars is not None
+    assert self._outjar is not None
+    assert self._configs is not None
+    cmd = [
+      'java', '-jar', self._proguard_jar_path,
+      '-forceprocessing',
+    ]
+    if self._test:
+      cmd += [
+        '-dontobfuscate',
+        '-dontoptimize',
+        '-dontshrink',
+        '-dontskipnonpubliclibraryclassmembers',
+      ]
+
+    if self._mapping:
+      cmd += [
+        '-applymapping', self._mapping,
+      ]
+
+    if self._libraries:
+      cmd += [
+        '-libraryjars', ':'.join(self._libraries),
+      ]
+
+    cmd += [
+      '-injars', ':'.join(self._injars)
+    ]
+
+    for config_file in self._configs:
+      cmd += ['-include', config_file]
+
+    # The output jar must be specified after inputs.
+    cmd += [
+      '-outjars', self._outjar,
+      '-dump', self._outjar + '.dump',
+      '-printseeds', self._outjar + '.seeds',
+      '-printusage', self._outjar + '.usage',
+      '-printmapping', self._outjar + '.mapping',
+    ]
+    return cmd
+
+  def GetInputs(self):
+    inputs = [self._proguard_jar_path] + self._configs + self._injars
+    if self._mapping:
+      inputs.append(self._mapping)
+    if self._libraries:
+      inputs += self._libraries
+    return inputs
+
+
+  def CheckOutput(self):
+    build_utils.CheckOutput(self.build(), print_stdout=True,
+                            stdout_filter=FilterProguardOutput)
+