Use NeedsManualRebaseline to disable tests.

BUG=577300
TBR=junov

Review URL: https://codereview.chromium.org/1615953004 .

Cr-Commit-Position: refs/heads/master@{#370789}

third_party/WebKit/LayoutTests/TestExpectations

@@ -222,9 +222,9 @@ crbug.com/542541 [ Debug ] virtual/trustedeventsdefaultaction/fast/events/click-
 crbug.com/542541 [ Debug ] virtual/pointerevent/fast/events/click-count.html [ Pass Failure ]
 
 # TODO(wkorman): crbug.com/577300 Uncomment the scalefactor expectations below once rebaseline bot is fixed.
-# crbug.com/495750 virtual/scalefactor200/fast/hidpi/static [ NeedsRebaseline ]
-# crbug.com/495750 virtual/scalefactor150/fast/hidpi/static [ NeedsRebaseline ]
-# crbug.com/495750 [ Win Linux ] virtual/scalefactor200withzoom/fast/hidpi/static [ NeedsRebaseline ]
+crbug.com/495750 virtual/scalefactor200/fast/hidpi/static [ NeedsManualRebaseline ]
+crbug.com/495750 virtual/scalefactor150/fast/hidpi/static [ NeedsManualRebaseline ]
+crbug.com/495750 [ Win Linux ] virtual/scalefactor200withzoom/fast/hidpi/static [ NeedsManualRebaseline ]
 crbug.com/495750 [ Mac Android ] virtual/scalefactor200withzoom/fast/hidpi/static [ Skip ]
 # TODO(oshima): Fix the popup's size adjustmenet.
 crbug.com/495750 virtual/scalefactor200/fast/hidpi/static/data-suggestion-picker-appearance.html [ Skip ]