Update from https://crrev.com/304121

build/android/pylib/instrumentation/test_jar.py

Index: build/android/pylib/instrumentation/test_jar.py
diff --git a/build/android/pylib/instrumentation/test_jar.py b/build/android/pylib/instrumentation/test_jar.py
index c81258f8aebecf6f8f5846ee8a2c9d0b80169823..d83d00a150e3178f29f4818eb9610b133798520c 100644
--- a/build/android/pylib/instrumentation/test_jar.py
+++ b/build/android/pylib/instrumentation/test_jar.py
@@ -23,7 +23,7 @@ sys.path.insert(0,
 import unittest_util # pylint: disable=F0401
 
 # If you change the cached output of proguard, increment this number
-PICKLE_FORMAT_VERSION = 2
+PICKLE_FORMAT_VERSION = 3
 
 
 class TestJar(object):
@@ -55,6 +55,16 @@ class TestJar(object):
     if not self._GetCachedProguardData():
       self._GetProguardData()
 
+  @staticmethod
+  def _CalculateMd5(path):
+    # TODO(jbudorick): Move MD5sum calculations out of here and
+    # AndroidCommands to their own module.
+    out = cmd_helper.GetCmdOutput(
+        [os.path.join(constants.GetOutDirectory(),
+                      'md5sum_bin_host'),
+        path])
+    return out
+
   def _GetCachedProguardData(self):
     if (os.path.exists(self._pickled_proguard_name) and
         (os.path.getmtime(self._pickled_proguard_name) >
@@ -64,7 +74,9 @@ class TestJar(object):
       try:
         with open(self._pickled_proguard_name, 'r') as r:
           d = pickle.loads(r.read())
-        if d['VERSION'] == PICKLE_FORMAT_VERSION:
+        jar_md5 = self._CalculateMd5(self._jar_path)
+        if (d['JAR_MD5SUM'] == jar_md5 and
+            d['VERSION'] == PICKLE_FORMAT_VERSION):
           self._test_methods = d['TEST_METHODS']
           return True
       except:
@@ -182,7 +194,8 @@ class TestJar(object):
 
     logging.info('Storing proguard output to %s', self._pickled_proguard_name)
     d = {'VERSION': PICKLE_FORMAT_VERSION,
-         'TEST_METHODS': self._test_methods}
+         'TEST_METHODS': self._test_methods,
+         'JAR_MD5SUM': self._CalculateMd5(self._jar_path)}
     with open(self._pickled_proguard_name, 'w') as f:
       f.write(pickle.dumps(d))