LayoutTests: Disabling media tests which fail on Mac swarming.

third_party/WebKit/LayoutTests/TestExpectations

Index: third_party/WebKit/LayoutTests/TestExpectations
diff --git a/third_party/WebKit/LayoutTests/TestExpectations b/third_party/WebKit/LayoutTests/TestExpectations
index 1cb0adfefacb5c711760e50e86372ef384a00b47..13feaeeb80c3ca05d041e0623f8ee1b25930869b 100644
--- a/third_party/WebKit/LayoutTests/TestExpectations
+++ b/third_party/WebKit/LayoutTests/TestExpectations
@@ -2858,3 +2858,9 @@ crbug.com/731018 [ Mac ] sensor/magnetometer.html [ Failure Pass ]
 crbug.com/731018 [ Mac ] sensor/orientation-sensor.html [ Failure Pass ]
 
 crbug.com/731035 [ Win ] virtual/new-remote-playback-pipeline/media/controls/video-controls-overflow-menu-hide-on-click-panel.html [ Failure Pass ]
+
+# More flaky tests on Mac
+crbug.com/731111 [ Mac ] http/tests/media/progress-events-generated-correctly.html [ Failure Pass Timeout ]
+crbug.com/731111 [ Mac ] http/tests/media/video-load-metadata-decode-error.html [ Failure Pass Timeout ]
+crbug.com/731111 [ Mac ] virtual/mojo-loading/http/tests/media/progress-events-generated-correctly.html [ Failure Pass Timeout ]
+crbug.com/731111 [ Mac ] virtual/mojo-loading/http/tests/media/video-load-metadata-decode-error.html [ Failure Pass Timeout ]