[Android] Allow gtests to pull app data off the device before clearing it.

build/android/pylib/gtest/gtest_test_instance.py

Index: build/android/pylib/gtest/gtest_test_instance.py
diff --git a/build/android/pylib/gtest/gtest_test_instance.py b/build/android/pylib/gtest/gtest_test_instance.py
index cea50160f51d9b086441a1297dc52b7740d464b6..ed1190fc469e38093f0280fc2b20e1e73a91b365 100644
--- a/build/android/pylib/gtest/gtest_test_instance.py
+++ b/build/android/pylib/gtest/gtest_test_instance.py
@@ -7,6 +7,7 @@ import os
 import re
 import shutil
 import sys
+import tempfile
 
 from pylib import constants
 from pylib.base import base_test_result
@@ -127,6 +128,17 @@ class GtestTestInstance(test_instance.TestInstance):
       logging.warning('No isolate file provided. No data deps will be pushed.');
       self._isolate_delegate = None
 
+    if args.app_data_files:
+      self._app_data_files = args.app_data_files
+      if args.app_data_file_dir:
+        self._app_data_file_dir = args.app_data_file_dir
+      else:
+        self._app_data_file_dir = tempfile.mkdtemp()
+        logging.critical('Saving app files to %s', self._app_data_file_dir)
+    else:
+      self._app_data_files = None
+      self._app_data_file_dir = None
+
   #override
   def TestType(self):
     return 'gtest'
@@ -232,6 +244,14 @@ class GtestTestInstance(test_instance.TestInstance):
     return self._apk_path
 
   @property
+  def app_file_dir(self):
+    return self._app_data_file_dir
+
+  @property
+  def app_files(self):
+    return self._app_data_files
+
+  @property
   def exe(self):
     return self._exe_path