Mark external/wpt/magnetometer/Magnetometer-iframe-access.https.html flaky

Also removed the stale expectation files on mac

TBR=thakis@chromium.org

Bug: 855222
Change-Id: Iaaaebfcb5dc00c0d1c42f3a2ecbb5bbfcbbbf57c
Reviewed-on: https://chromium-review.googlesource.com/1112949Reviewed-by: Xianzhu Wang <wangxianzhu@chromium.org>
Commit-Queue: Xianzhu Wang <wangxianzhu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#569918}

third_party/WebKit/LayoutTests/TestExpectations

@@ -4728,6 +4728,7 @@ crbug.com/854910 [ Mac ] fast/scroll-behavior/smooth-scroll/track-scroll.html [
 crbug.com/854910 [ Mac ] virtual/scroll_customization/fast/scroll-behavior/smooth-scroll/track-scroll.html [ Failure Pass ]
 crbug.com/855222 [ Mac ] external/wpt/orientation-sensor/AbsoluteOrientationSensor-iframe-access.https.html [ Failure Pass ]
 crbug.com/855222 [ Mac ] external/wpt/orientation-sensor/RelativeOrientationSensor-iframe-access.https.html [ Failure Pass ]
+crbug.com/855222 [ Mac ] external/wpt/magnetometer/Magnetometer-iframe-access.https.html [ Failure Pass ]
 
 # Sheriff 2018-06-22
 crbug.com/855055 [ Mac ] virtual/threaded/animations/interpolation/svg-stroke-dasharray-interpolation.html [ Pass Timeout ]

third_party/WebKit/LayoutTests/platform/mac-mac10.10/external/wpt/magnetometer/Magnetometer-iframe-access.https-expected.txt

-This is a testharness.js-based test.
-PASS Magnetometer: sensor is suspended and resumed when focus traverses from to cross-origin frame
-PASS Magnetometer: sensor is not suspended when focus traverses from to same-origin frame
-FAIL UncalibratedMagnetometer: sensor is suspended and resumed when focus traverses from to cross-origin frame assert_true: expected true got false
-FAIL UncalibratedMagnetometer: sensor is not suspended when focus traverses from to same-origin frame assert_true: expected true got false
-Harness: the test ran to completion.
-

third_party/WebKit/LayoutTests/platform/mac-mac10.11/external/wpt/magnetometer/Magnetometer-iframe-access.https-expected.txt

-This is a testharness.js-based test.
-PASS Magnetometer: sensor is suspended and resumed when focus traverses from to cross-origin frame
-FAIL Magnetometer: sensor is not suspended when focus traverses from to same-origin frame assert_true: Not expecting event, but got reading event expected true got false
-FAIL UncalibratedMagnetometer: sensor is suspended and resumed when focus traverses from to cross-origin frame promise_test: Unhandled rejection with value: object "Error: Call reset() before initialize()."
-FAIL UncalibratedMagnetometer: sensor is not suspended when focus traverses from to same-origin frame promise_test: Unhandled rejection with value: object "Error: Call reset() before initialize()."
-Harness: the test ran to completion.
-

third_party/WebKit/LayoutTests/platform/mac-mac10.12/external/wpt/magnetometer/Magnetometer-iframe-access.https-expected.txt

-This is a testharness.js-based test.
-PASS Magnetometer: sensor is suspended and resumed when focus traverses from to cross-origin frame
-PASS Magnetometer: sensor is not suspended when focus traverses from to same-origin frame
-FAIL UncalibratedMagnetometer: sensor is suspended and resumed when focus traverses from to cross-origin frame assert_true: expected true got false
-FAIL UncalibratedMagnetometer: sensor is not suspended when focus traverses from to same-origin frame assert_true: expected true got false
-Harness: the test ran to completion.
-

third_party/WebKit/LayoutTests/platform/mac-retina/external/wpt/magnetometer/Magnetometer-iframe-access.https-expected.txt

-This is a testharness.js-based test.
-PASS Magnetometer: sensor is suspended and resumed when focus traverses from to cross-origin frame
-FAIL Magnetometer: sensor is not suspended when focus traverses from to same-origin frame assert_true: Not expecting event, but got reading event expected true got false
-FAIL UncalibratedMagnetometer: sensor is suspended and resumed when focus traverses from to cross-origin frame promise_test: Unhandled rejection with value: object "Error: Call reset() before initialize()."
-FAIL UncalibratedMagnetometer: sensor is not suspended when focus traverses from to same-origin frame promise_test: Unhandled rejection with value: object "Error: Call reset() before initialize()."
-Harness: the test ran to completion.
-

third_party/WebKit/LayoutTests/platform/mac/external/wpt/magnetometer/Magnetometer-iframe-access.https-expected.txt

-This is a testharness.js-based test.
-PASS Magnetometer: sensor is suspended and resumed when focus traverses from to cross-origin frame
-FAIL Magnetometer: sensor is not suspended when focus traverses from to same-origin frame assert_true: Not expecting event, but got reading event expected true got false
-FAIL UncalibratedMagnetometer: sensor is suspended and resumed when focus traverses from to cross-origin frame promise_test: Unhandled rejection with value: object "Error: Call reset() before initialize()."
-FAIL UncalibratedMagnetometer: sensor is not suspended when focus traverses from to same-origin frame promise_test: Unhandled rejection with value: object "Error: Call reset() before initialize()."
-Harness: the test ran to completion.
-