lint: Fix warnings and errors.

Manually revised lint warnings and fixed most of them.
Only 211 lint issues left after this change is merged.

BUG=none
TEST=make test

Change-Id: I12a57ce1ef4f442bd8e5f2ccd2284b8b6258e928
Reviewed-on: https://chromium-review.googlesource.com/241392
Reviewed-by: Hung-Te Lin <hungte@chromium.org>
Commit-Queue: Hung-Te Lin <hungte@chromium.org>
Tested-by: Hung-Te Lin <hungte@chromium.org>
diff --git a/py/toolkit/installer.py b/py/toolkit/installer.py
index 8465433..37f1c5d 100755
--- a/py/toolkit/installer.py
+++ b/py/toolkit/installer.py
@@ -97,7 +97,7 @@
 ]
 
 
-class FactoryToolkitInstaller():
+class FactoryToolkitInstaller(object):
   """Factory toolkit installer.
 
   Args:
@@ -181,13 +181,11 @@
           '***' % self._dest)
     if self._dest == self._system_root:
       if self._no_enable:
-        ret += (
-                '\n*** Factory tests will be disabled after this process is '
+        ret += ('\n*** Factory tests will be disabled after this process is '
                 'done, but\n*** you can enable them by creating the factory '
                 'enabled tag:\n***   %s\n***' % self._tag_file)
       else:
-        ret += (
-                '\n*** After this process is done, your device will start '
+        ret += ('\n*** After this process is done, your device will start '
                 'factory\n*** tests on the next reboot.\n***\n*** Factory '
                 'tests can be disabled by deleting the factory enabled\n*** '
                 'tag:\n***   %s\n***' % self._tag_file)