Use exception instead of sys.exit().

Addresses a review comment from frankf at https://codereview.chromium.org/157743004/

BUG=142642

Review URL: https://codereview.chromium.org/154153008

git-svn-id: http://src.chromium.org/svn/trunk/src/build@250302 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

android/pylib/gtest/test_package_exe.py

@@ -123,19 +123,17 @@ class TestPackageExecutable(TestPackage):
     else:
       target_name = self.suite_path + '_stripped'
       if not os.path.isfile(target_name):
-        logging.critical('Did not find %s, build target %s',
+        raise Exception('Did not find %s, build target %s' %
-                         target_name, self.suite_name + '_stripped')
+                        (target_name, self.suite_name + '_stripped'))
-        sys.exit(1)
 
       target_mtime = os.stat(target_name).st_mtime
       source_mtime = os.stat(self.suite_path).st_mtime
       if target_mtime < source_mtime:
-        logging.critical(
+        raise Exception(
             'stripped binary (%s, timestamp %d) older than '
-            'source binary (%s, timestamp %d), build target %s',
+            'source binary (%s, timestamp %d), build target %s' %
-            target_name, target_mtime, self.suite_path, source_mtime,
+            (target_name, target_mtime, self.suite_path, source_mtime,
-            self.suite_name + '_stripped')
+             self.suite_name + '_stripped'))
-        sys.exit(1)
 
     test_binary = constants.TEST_EXECUTABLE_DIR + '/' + self.suite_name
     adb.PushIfNeeded(target_name, test_binary)