UserAgent: Mozilla/5.0 (Windows NT 6.3; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/69.0.3497.100 Safari/537.36

Steps to reproduce the problem:
1. Enable the 'Generic Sensor', 'Generic Sensor Extra Classes' and 'Experimental Web Platform features' in chrome://flags.
2.  Access https://intel.github.io/generic-sensor-demos/sensor-tester/build/bundled/accelerometer, run "Test +X gravity" when device is at rest on a leveled surface and right edge of the device points towards the sky

3. Same issue happens with the following tests:
3.1: Access https://intel.github.io/generic-sensor-demos/sensor-tester/build/bundled/accelerometer, run the tests:
   (1): Test +X gravity
   (2): Test -X gravity
   (3): Test +Y gravity
   (4): Test -Y gravity
3.2 Access https://intel.github.io/generic-sensor-demos/sensor-tester/build/bundled/gyroscope, run the tests:
   (1)： Test +X angular velocity
   (2)： Test -X angular velocity
   (3)： Test +Y angular velocity
   (4)： Test -Y angular velocity

What is the expected behavior?
x and y axes should correct. Access https://intel.github.io/generic-sensor-demos/sensor-tester/build/bundled/accelerometer, and run "Test +X gravity", the test should pass when device is at rest on a leveled surface and right edge of the device points towards the sky.

What went wrong?
x and y axes are reversed. Access https://intel.github.io/generic-sensor-demos/sensor-tester/build/bundled/accelerometer, and run "Test +X gravity", the test passes when device is at rest on a leveled surface and top edge of the device points towards the sky.

Did this work before? Yes 69.0.3464.0

Chrome version: 71.0.3555.0  Channel: canary
OS Version: Google_Samus.6300.174.0
Flash Version: