pep8: Ignore line break before binary operator

PEP8 has switched its guidance [1] for where a line break should occur
in relation to a binary operator, so don't raise this warning for
new code and update the code base to follow the new style.

[1] https://www.python.org/dev/peps/pep-0008/#should-a-line-break-before-or-after-a-binary-operator

wa/workloads/idle.py

@@ -88,6 +88,6 @@ class IdleWorkload(Workload):
                 self.target.sleep(1)
         if self.screen_off and self.old_screen_state:
             self.target.ensure_screen_is_on()
-        elif (self.target.os == 'android' and
-                not self.screen_off and not self.old_screen_state):
+        elif (self.target.os == 'android'
+                and not self.screen_off and not self.old_screen_state):
             self.target.ensure_screen_is_off()

wa/workloads/speedometer/__init__.py

@@ -259,8 +259,8 @@ class Speedometer(Workload):
         while not benchmark_complete:
             if self.target_file_was_created(local_storage):
                 if (
-                    iterations % (find_period_s // sleep_period_s) == 0 or
-                    not local_storage_seen
+                    iterations % (find_period_s // sleep_period_s) == 0
+                    or not local_storage_seen
                 ):
                     # There's a chance we don't see the localstorage file immediately, and there's a
                     # chance more of them could be created later, so check for those files every ~30